Speaker: Sharon Hammes-Schiffer

Title: Multicomponent Quantum Chemistry: Integrating Electronic and Nuclear Quantum Effects

Synopsis: The nuclear-electronic orbital (NEO) approach treats select nuclei, typically protons, quantum mechanically on the same level as the electrons with multicomponent density functional theory (DFT) or wavefunction methods such as coupled cluster. Nuclear quantum effects and non-Born-Oppenheimer effects are directly included in calculations of geometries, frequencies, and dynamics. Excited electronic, proton vibrational, and electron-proton vibronic states are calculated with NEO time-dependent DFT.

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Speaker: Trygve Helgaker

Title: Egil Hylleraas — A Pioneer of Computational Quantum Mechanics

Synopsis: The Norwegian physicist Egil A. Hylleraas (1898–1965) performed a number of pioneering computational studies in the early days of quantum mechanics, including accurate calculations on helium (confirming the validity of quantum mechanics for two particles) and the first calculation of the cohesive energy of a crystal. Many techniques introduced by Hylleraas are in use today. In this talk, an overview is given of the life and career of Hylleraas, the founding father of quantum chemistry in Norway.

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Speaker: Peter Schwerdtfeger

Title: The Year of the Periodic Table - Going Superheavy

Synopsis: The first Periodic Table was proposed by Mendeleev in 1869 on the basis of arranging the elements in ascending order of atomic weight and grouping them by similarity of chemical properties. At that time it was not known how far in the atomic weight we can go before the elements become too unstable and radioactively decay. How far can we go? Where does the Periodic Table end? Can we do chemistry with such exotic elements? What is the chemical and physical behavior of these exotic elements?

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Speaker: Sylvio Canuto

Title: Environment Contribution to Molecular Spectroscopy, Reactivity and Photochemistry

Synopsis: Using QM/MM methods with both Monte Carlo and Born-Oppenheimer molecular dynamics different applications have been made in spectroscopy and reactivity both in regular liquid environment as well as in supercritical condition. A critical review will be presented based on a large variety of applications on absorption and emission spectroscopy, magnetic shielding related to NMR experiments, excited state dynamics of simple molecules, simple chemical reactions as well as some photophysical processes.

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Speaker: Ilaria Ciofini

Title: Modeling Photo-Responsive systems using combined classical and DFT approaches

Synopsis: In this talk, we present different theoretical tools ranging from classical to quantum approaches in either molecular or periodic formalisms to model and describe photo-responsive materials (such as mechanochromic systems) or light induced phenomena (such as aggregation induced emission).

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Speaker: Pavlo Dral

Title: Quantum Chemistry Assisted by Machine Learning

Synopsis: Machine learning (ML) can assist quantum chemical research in a variety of ways, e.g. to improve quantum chemical (QC) methods (e.g. Δ-learning approach and semiempirical QC parameter learning) and to significantly reduce the number of required high-level QC computations in rovibrational spectrum simulations and nonadiabatic excited-state dynamics.

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Speaker: Oleg Prezhdo

Title: Time-Domain Modeling of Excited State Dynamics in Halide Perovskites

Synopsis: We develop approaches combining nonadiabatic molecular dynamics and real-time TDDFT to study excited state dynamics in various nanoscale materials. After an introduction to the methods development, the talk will focus on hybrid organic-inorganic perovskites, which are very interesting and rich materials with great potential for solar energy and other applications. We will also discuss new phenomena, predicted and modelled in our group, such as Auger-assisted and plasmon-driven electron transfer.

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Speaker: Thomas Albrecht-Schmitt

Title: An Unexpected Route to the Formation of Covalent Bonds in Cerium and Berkelium Coordination Complexes

Synopsis: An unexpected plane of covalency has been found in a special family of cerium and berkelium coordination complexes.

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Speaker: Shuhua Li

Title: Generalized energy-based fragmentation approach for large molecules and condensed phase systems

Synopsis: The extension of the linear scaling method – GEBF (generalized energy-based fragmentation) approach – to treat metal-containing large molecules and condensed phase systems will be reported.

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Speaker: Cecilia Clementi

Title: Machine Learning Models for Biomolecular Dynamics

Synopsis: We combine statistical mechanics with machine learning methods to derive molecular models able to reproduce the essential information contained both in microscopic simulation and experimental measurements.

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Speaker: Damien Laage

Title: Water at electrified graphene interfaces: structure, dynamics, vibrational SFG spectroscopy and consequences for electron transfer reactions

Synopsis: Water's properties at electrified interfaces are central in e.g. electrochemistry. We present the main results of our study of water/electrified graphene interfaces. We show that the interfacial water molecules' structural and dynamical properties vary non-monotonically with the applied potential. We indicate how water vibrational SFG spectra depend on interfacial and subsequent water layers’ contributions. Finally, key consequences for interfacial electron transfer reactions are discussed.

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Speaker: Katharina Boguslawski

Title: Simplified Coupled Cluster Methods for f0 Actinide Compounds

Synopsis: Conceptually different approaches to model strongly-correlated electrons exploit two-electron functions as fundamental building blocks of the electronic wavefunction, also called geminals. One example is the Antisymmetric Product of 1-reference-orbital Geminals (AP1roG), which is equivalent to the pair-Coupled-Cluster Doubles ansatz. We will discuss the performance of various AP1roG-based methods in modeling electronic structures of ground and excited states for molecules containing actinides.

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Speaker: Petko Petkov

Title: Computational modeling of H/H+ migration in porous and layered materials

Synopsis: a H+ from acidic OH – groups in the zeolites, containing TM clusters.

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Speaker: Marivi Fernandez-Serra

Title: Machine learning a highly accurate exchange and correlation functional of the electronic density

Synopsis: We propose a new framework to create density functionals for electronic structure calculations by using supervised machine learning. These machine learned functionals are built on top of well-established and physically motivated density functionals and are designed to correct their shortcomings. We show that our functional can lift generalized gradient methods to the accuracy of coupled cluster calculations , all while being highly data-efficient and somewhat transferable.

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Speaker: Dominika Zgid

Title: Finite temperature Green's function theories for periodic systems

Synopsis: We perform periodic calculations with the Green's function second order and GW method and discuss possible bottlenecks and remedies that can speed up these calculations. We evaluate momentum-resolved spectral functions and band gaps from bare and self-consistent second order perturbation theory for insulating periodic solids. We establish that, for systems with large gap sizes, both bare and self-consistent perturbation theory yield reasonable gaps.

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Speaker: Han-Shi Hu

Title: Bonding Pattern Change Induced by Relativistic Effects

Synopsis: The periodic law was recently known to be affected significantly by relativity in addition to the nonrelativistic description. Here we report that relativistic effects can change the bonding pattern of the diatomic molecules M2 based on the group 6 element as well as the coinage metal elements.

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Speaker: Jianping Xiao

Title: Toward Computational Design of Catalysts for CO2 Selective Reduction via Reaction Phase Diagram Analysis

Synopsis: A simple and effective theoretical analysis of “reaction phases diagram” to understand the selectivity of CO2 reduction, based on the principle of reaction free energies with sequential priority is proposed.On the basis of reaction free energies' analysis, the selectivity trends of CO2 reduction to methane, methanol, and ethanol from a number of experiments are discussed. Finally, the selectivity trends with a computer algorithm of searching full reaction pathways are confirmed.

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Speaker: Koji Tsuda

Title: Expanding the horizon of automated metamaterials discovery via quantum annealing

Synopsis: Complexity of materials designed by machine learning is currently limited by the inefficiency of classical computers. We show how quantum annealing can be incorporated into automated materials discovery and conduct a proof-of-principle study on designing complex thermofunctional metamaterials.

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Speaker: Thomas Markland

Title: Accurate and Efficient Non-adiabatic Quantum Dynamics using Master Equations

Synopsis: The exact treatment of real time nonadiabatic quantum dynamics in condensed phase chemical systems remains a significant challenge that spurs the ongoing development of approximate methods that are accurate, efficient, and can treat large systems with a wide range of different forms of interactions. Quantum-classical trajectory based methods provide some of the most appealing solutions to this problem that offer a hierarchy of approaches with different balances between accuracy and computational

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Speaker: Michael Patzschke

Title: Combined computational and spectroscopical analysis of tetravalent f-element complexes

Synopsis: We present DFT-based electron-density analysis of the bonding in amidinate and Schiff-base actinide complexes. We will discuss experimental and computational NMR results for. Results of multi-reference calculations of some of these complexes will be shown and UV/Vis and TRLFS spectra will be discussed.

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Speaker: Alston Misquitta

Title: Can we derive many-body non-additive polarization energies from 1-body properties and 2-body energies only?

Synopsis: We demonstrate how it is possible to derive the many-body polarization energies in strongly polar systems from ISA-based molecular properties (multipoles and polarizabilities) and two-body charge-delocalization energies defined using regularized-SAPT(DFT). By constructing a series of water models, these DIFF models, are shown to be competitive with some of the most elaborate water models currently available. This methodology is general and can be used to derive many-body models for any system

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Speaker: Filippo Lipparini

Title: A general linear scaling implementation for polarizable embedding methods

Synopsis: A general, linear scaling implementation of polarizable QM/MM methods is presented. Such a strategy is not only very efficient, allowing for the treatment of very large embeddings, but also completely general, as it is in principle able to deal with arbitrary order static multipoles and different polarization models.

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Speaker: Luuk Visscher

Title: Relativistic coupled cluster for a new generation of supercomputers

Synopsis: I will present a new implementation of relativistic coupled cluster algorithms that is based on the efficient GPU-adapted and parallel ExaTensor library of Lyakh. I will discuss our design choices, required starting data, present capabilities and performance of the code. I will also give an outlook of our possible further developments. The code will be provided as open-source with the December 2019 release of DIRAC

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Speaker: Krzystof Szalewicz

Title: From molecular properties to intermolecular interaction potentials

Synopsis: It will be shown that if molecular properties of monomers are properly distributed among atoms, the resulting asymptotic expansions of interaction energies provide an excellent approximation of these energies down to intermonomer separations about 1.5 times the separation of the van der Waals minimum. This finding is important for development of intermolecular force fields both from first principles and in semiepirical ways.

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Speaker: Jean-Philip Piquemal

Title: Scalable polarizable molecular dynamics using Tinker-HP

Synopsis: Tinker-HP (http://tinker-hp.ip2ct.upmc.fr/) is a CPU based, double precision, massively parallel package dedicated to long polarizable molecular dynamics simulations and to polarizable QM/MM. New results are presented both in classical polarizable and hybrid QM/MM (with full variational polarizable embedding) simulations.

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Speaker: Andre Severo Pereira Gomes

Title: Relativistic equation of motion coupled cluster based on four-compoment Hamiltonians

Synopsis: In this contribution we discuss our recent implementation in the Dirac program of the equation of motion coupled cluster method for excitation energies (EOM-EE-CCSD), single electron attachment (EOM-EA-CCSD) and single electron detachment (EOM-IP-CCSD) based on four-component Hamiltonians. We showcase the method with calculations of low-lying electronic states of halogen monoxides, excited and ionized of the plutonium dioxide molecule, and ionization energies of halide-water droplets systems.

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Speaker: Andreas Hesselmann

Title: Intermolecular interaction energies from fourth order many-body perturbation theory. Impact of individual electron correlation contributions.

Synopsis: The performance of Moller-Plesset perturbation theory methods for describing intermolecular interaction energies is investigated with the focus on illuminating the impact of individual electron correlation energy contributions in fourth order.

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Speaker: Debashree Ghosh

Title: Photo-processes in biological systems – Need for hybrid QM/MM with polarization

Synopsis: In this talk, I will discuss the strategies for including polarization in hybrid QM/MM method for biological and condensed phases. I will also discuss our recent efforts towards development of machine learning based polarizable force fields.

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Speaker: Hiromi Nakai

Title: Relativistic density functional theory with picture-change corrected electron density

Synopsis: We developed the picture-change corrected (PCC) relativistic DFT that relies on a unitary-transformed density operator as well as a unitary-transformed Hamiltonian. Furthermore, we examined the techniques to reduce the computational cost to evaluate the PCC density. This approach was implemented into the relativistic program package developed in the author’s group, namely, RAQET. In the presentation, I will explain the theoretical aspects s, implementation, and some numerical applications.

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Speaker: Malgorzata M. Szczesniak

Title: New Meta-GGA "Workhorses" in Transition Metal Chemistry and SAPT

Synopsis: The recently developed DFT meta-GGAs and their hybrids, such as SCAN, SCAN0, MVS, wB97M-V, and our own LC-PBETPSS-D3 promise improvement over the well-established GGAs and hybrid GGAs developed some 10-20 years ago. Are these promises fulfilled? This work examines performance of these new methods in transition-metal chemistry and catalysis. The results are rationalized in terms of fractional charge/fractional spin errors. The issue of suitability of these new meta-GGAs in SAPT is also explored.

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Speaker: Ksenia Bravaya

Title: Simulating Electron Transfer in Biomolecules: the Role of Polarization and Long-range Electrostatic Interactions

Synopsis: In this talk, the challenges theoretical chemistry faces when one wants to describe energetics and dynamics of electron transfer in complex heterogeneous media, as proteins, will be discussed. Specifically, the role of environment polarization and long-range electrostatic interactions on the for accurate evaluation such quantities as redox potentials, charge-transfer states excitation energies, and electronic couplings, using a cryptochrome protein as a model system, will be addressed.

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Speaker: Florian Weigend

Title: NMR Shielding Tensors and Shifts in the Local Exact Two-Component Theory

Synopsis: An efficient implementation of scalar-relativistic NMR shielding tensors based on the exact two-component theory (X2C) in the diagonal local approximation to the unitary decoupling matrix (DLU) is presented. Efficiency and accuracy are demonstrated for heavy-element compounds with more than 120 atoms. Further, extensions for the all-electron relativistic Karlsruhe basis sets are presented and their quality is assessed.

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Speaker: Ali Alavi

Title: Non-unitary Quantum Chemistry

Synopsis: We investigate the utility of non-unitary similarity transformations, based on Jastrow or Gutzwiller factorisation of the electronic wavefunction. Such factorisations generally lead to non-Hermitian effective Hamiltonians which contain three-body interactions. Such Hamiltonians are treatable via the projective FCIQMC technique, which does not suffer from the non-Hermitian characteristic of the Hamiltonian, nor do the 3-body terms present an insuperable obstacle.

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Speaker: David Ceperley

Title: Melting of the 2D Wigner Crystal

Synopsis: We have performed restricted path integral Monte Carlo (PIMC) simulations for the spin-polarized and unpolarized homogeneous electron gas in two dimension at low densities and low temperatures. We obtain the conditions for stability of the Wigner crystal by directly observing freezing and melting.

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Speaker: Edit Matyus

Title: Ultra-precise computations for molecular paradigms

Synopsis: Ultra-precise computations accounting for non-adiabatic, relativistic, and radiative effects are necessary to understand and make use of ultra-precise measurements of molecular transition energies (of sub-MHz uncertainty) made possible by recent developments in the experimental control and manipulation of molecular states.

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Speaker: Cyrus Umrigar

Title: Semistochastic Heatbath Configuration Interaction Method and Orbital Optimization

Synopsis: SHCI is a variant of Selected Configuration Interaction plus Perturbation Theory (SCI+PT) methods such as CIPSI. I will describe the two key innovations make it faster than other SCI+PT methods, and overcome the memory bottleneck in the perturbative step. The method has been applied to challenging molecular systems with more than 2 billion variational determinants and trillions of perturbative determinants. Recent work on improving the efficiency of orbital optimization is described.

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Speaker: Mark Tuckerman

Title: A path-integral sampling (trajectory-free) approach to the calculation of quantum time correlation functions

Synopsis: A new path-integral based sampling scheme is presented for the calculation of symmetrized quantum time correlation functions. The approach employs a transformation to sum and difference variables between forward and backward complex-time paths. It is shown that a formal integration over the difference variables yields an integral over the sum variables with a positive-definite distribution that can be sampled. Approximations to this formal integral are investigated and examples presented.

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Speaker: Kirk Peterson

Title: On the Development of Accurate Gaussian Basis Sets for f-Block Elements - Initial Efforts for F12 Correlation Consistent Basis Sets for Uranium

Synopsis: This talk will investigate the efficiency of F12 methods at recovering correlation effects of electrons in the compact inner valence orbitals found in lanthanides and actinides, as well as the important outer-core electrons. Initial results for geometries and relative energies will be presented at the CCSD(T)-F12 level of theory using existing cc-pVnZ-PP basis sets for selected uranium-containing molecules. Preliminary design of new F12 basis sets for uranium will also be discussed.

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Speaker: Eric Neuscamman

Title: Variational Excited States in DFT, QMC, and Quantum Chemistry

Synopsis: We will discuss uses for excited state variational principles across a wide range of electronic structure contexts, including mean field theory, density functional theory, multi-reference theory, and quantum Monte Carlo.

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Speaker: Jian Liu

Title: Path integral Liouville dynamics & a unified framework for path integral molecular dynamics

Synopsis: We first show a unified second-order scheme for constructing simple, robust and accurate algorithms for typical thermostats for exact quantum statistics for the canonical ensemble. The scheme consistently improves the efficiency for evaluating all quantum thermodynamic properties. We then show path integral Liouville dynamics (PILD) that has the two important properties: conserves the quantum canonical distribution and recovers exact thermal correlation functions (of even nonlinear operators).

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Speaker: David Tew

Title: Principal Domains in Local Correlation Theory

Synopsis: The computational efficiency of local correlation methods is strongly dependent on the size of the domain of functions used to expand local correlating orbitals. Here we define a principal domain of order m as the subset of m one-particle functions that provides the best support for a given n-electron wavefunction. We present a linear scaling greedy algorithm for obtaining principal domains of PAOs and demonstrate its utility in the context of PNO local correlation theory.

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Speaker: Sandeep Sharma

Title: Polynomial scaling multireference methods

Synopsis: I will present methods to calculate the electronic structure of challenging systems including metalloenzymes and quantum materials using methods that scale polynomially with the size of the problem.

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Speaker: Nancy Makri

Title: Modular Quantum and Rigorous Quantum-Classical Real-Time Path Integral Methods

Synopsis: The quantum-classical path integral (QCPI) offers a rigorous, yet efficient way of combining a quantum mechanical description of a system with a classical trajectory treatment of its complex polyatomic environment without any assumptions or adjustable parameters. Further, a modular decomposition of the path integral (MPI) allows fully quantum mechanical calculations of coupled electron-vibration dynamics in systems characterized by a quasi-one-dimensional topology with linear scaling.

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Speaker: Hans-Joachim Werner

Title: Explicitly correlated local coupled-cluster methods for large molecules

Synopsis: We review recent developments of explicitly correlated coupled-cluster methods for large closed-shell and open-shell molecules. Benchmark calculations for reaction energies, intermolecular interaction energies, ionization energies, and radical stabilization energies are presented, which demonstrate the outstanding accuracy and efficiency of the methods. Finally, we give an outlook to the treatment of large transition metal clusters using new CASSCF and (multi-state) PNO-CASPT2 implementations.

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Speaker: Peter Gill

Title: Q-MP2-OS: A new approach to correlation using quadrature

Synopsis: Second-order Moller-Plesset perturbation (MP2) theory is one of the simplest approaches to electron correlation but it is difficult to parallelize on large numbers of processing units and its cost scales quintically with the size of the system. We will present a quadrature-based approximation (Q-MP2) which is highly parallelizable and whose computational cost grows only quadratically with system size.

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Speaker: Peter Saalfrank

Title: Molecules driven by light: Electron and nuclear dynamics

Synopsis: In molecules driven by light, electrons and nuclei are set in motion. In the talk, correlated wavefunction methods will be used to describe post-excitation electron dynamics, time-dependent correlation functions for vibronic spectra, and, finally, non-adiabatic surface hopping techniques for photochemical reactions.

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Speaker: Robert Paton

Title: New Mechanisms and Concepts for Organic Reactivity and Enantioselectivity From Computations

Synopsis: The mechanistic-driven discovery of new catalyst structures from combined theoretical and experimental studies will be described. Recent applications include phase-transfer asymmetric fluorinations and new ligands for metal-catalyzed cycloisomerizations.

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Speaker: Olexandr Isayev

Title: Neural networks learning quantum chemistry

Synopsis: We will present a fully transferable deep learning molecular potential that is applicable to complex and diverse molecular systems. Focusing on parametrization for organic molecules, we have developed ANI neural network potential which is highly accurate compared to reference QM calculations at speeds 10^7 faster.

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Speaker: Todd J. Martinez

Title: Potential Energy Surfaces and Nonadiabatic Dynamics in Photoactive Proteins from First Principles

Synopsis: We discuss graphical processing unit (GPU)-based methods for efficient and accurate calculations of excited states in proteins. We present an application to the excited state dynamics of the channelrhodopsin-2 light-activated ion channel that is used in optogenetics.

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Speaker: Stefaan Cottenier

Title: Po-containing molecules in fission and fusion reactors

Synopsis: Fission and fusion reactors can only play a role in the future energy landscape if they are inherently safe by design. A remaining issue is the undesired production of radiotoxic 210-Po. This radiotoxicity complicates experimental investigations, and a quantum chemistry approach is a sound alternative. This work illustrates how quantum chemistry for molecules can have impact on engineering decisions for large facilities.

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Speaker: Kathrin Hopmann

Title: Is Your Mechanism Correct? Insights into Hydrogenation and Carboxylation Reactions

Synopsis: Computationally proposed reaction mechanisms are not always sufficiently validated. I will discuss the state-of-the-art in DFT modelling of metal-catalyzed reactions and show approaches to validate proposed pathways. Discussed examples include mechanistic studies of metal-catalyzed hydrogenation and CO2 incorporation reactions. Based on our work, we propose trends as to when metal-CO2 interactions should be expected during C-CO2 bond formation with late transition metals.

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Speaker: Johannes Hachmann

Title: A Machine Learning Shortcut to Physics-Based Modeling and Simulations

Synopsis: We will show how we employ machine learning to develop data-derived prediction models that are alternatives to physics-based models, and how we utilize them in massive-scale hyperscreening studies at a fraction of the cost.

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Speaker: Regina de Vivie-Riedle

Title: Photostability of Uracil affected by RNA environment or shaped light

Synopsis: Uracil is a key unit of nucleotides in RNA, and one of the crucial players in processing genetic information. It is susceptible to light, which can lead to unwanted modifications as delaying the fast relaxation process through conical intersections which secures photostability. Shaped light is used to investigate to which extend nuclear and electron dynamics can be influenced at the conical intersection and whether there is a connection to the response of Uracil to its the natural environment.

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Speaker: Helene Bolvin

Title: Magnetic coupling between f centers from first principles.

Synopsis: The magnetic coupling between two 4f or 5f centers is calculated using highly correlated methods and the coupling scheme is analyzed using Spin Hamiltonians.

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Speaker: Per-Ola Norrby

Title: Selectivity models for chemical synthesis

Synopsis: Two types of selectivity models will be presented. The first is virtual screen for optimal selectivity in asymmetric catalysis, built upon our Q2MM method for building transition state force fields. The second is a machine learning model based on computed descriptors, to determine regioselectivity in C-H functionalization reactions.

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Speaker: Alexandre Tkatchenko

Title: Towards Exact Molecular Dynamics Simulations with Quantum Chemistry and Machine Learning

Synopsis: I will discuss an efficient symmetric gradient-domain machine learning (sGDML) approach for constructing next-generation CCSD(T)-quality interatomic force fields for molecules. The sGDML implementation is able to reproduce global potential-energy surfaces of intermediate-sized molecules with an accuracy of 0.1 kcal/mol using only few hundred molecular conformations for training.

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Speaker: Leticia Gonzalez

Title: Excited state dynamics of transition metal complexes using efficient trajectory surface hopping methods

Synopsis: The complex interplay of internal conversion and intersystem crossing dynamics in transition metal complexes can be described with trajectory surface hopping methods, e.g. as implemented our SHARC code. This presentation shows several examples of excited state dynamics in transition metals. It also presents a novel simple approach using a linear vibronic coupling method that allowing to reduce computational times by orders of magnitude, so that different methodological benchmarks can be investi

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Speaker: Juha Vaara

Title: Computations of Small Physical Effects in Nuclear Magnetic Resonance

Synopsis: Interesting physics remain be explored in modern NMR: 1. Computations reproduce quantitatively the spin-spin coupling over 129Xe-3He van der Waals bond, measured in a co-magnetometer. 2. Experimental found magnetic field-dependent 59Co shielding is backed up by non-linear response theory. 3. Nuclear spin-induced magnetochiral birefringence/dichroism are new proposed nuclear magneto-optic effects. 4. Multiscale simulations can be used to investigate details of spin-exchange optical pumping.

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Speaker: Benedetta Mennucci

Title: The protein is the key: the unique chemistry of biological pigments revealed by a multiscale strategy

Synopsis: Molecular pigments behave differently when they are embedded in a protein and this is at the origin of some of the most important biological functions. The molecular mechanisms determining such a new behavior can only be revealed by computational approaches which are able to couple the structural, electronic and dynamic properties of the pigments and the protein. In this talk, examples of this multiscale modeling will be discussed for pigment-protein complexes present in plants and bacteria.

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Speaker: Volker Deringer

Title: From Machine-Learning Interatomic Potentials to Atomic-Scale Materials Science

Synopsis: Machine learning (ML) based interatomic potentials are an increasingly popular approach for describing potential-energy surfaces. In this talk, I will demonstrate that they are promising tools to solve challenging problems in atomic-scale materials science. I will first showcase ML-driven simulations of amorphous (non-crystalline) functional materials, and will then discuss how ML potential fitting can be unified with crystal-structure searching and prediction.

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Speaker: Graham Worth

Title: Simulating Non-adiabatic Photochemistry using Grids and Gaussians

Synopsis: Solving the time-dependent Schroedinger equation is necessary to describe the time-evolution of photo-excited molecules. These calculations required huge computer resources due to the inherently coupled nature of the nuclear and electronic motion. State-of-the-art methods to solve this problem will be presented, namely the MCTDH algorithm with model Hamiltonians, and the DD-vMCG method that uses Gaussian wavepackets and on-the-fly potentials for greater flexibility.

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Speaker: Michal Jaszunski

Title: Nuclear magnetic dipole moments from NMR experiments

Synopsis: We discuss new values of nuclear magnetic dipole moments, obtained from accurate absolute shielding constants and experimental NMR data, for a series of nuclei. The generally accepted literature values of magnetic moments were for many isotopes derived from NMR spectra. However, in the procedure applied to determine the moments of bare nuclei the effects of the molecular electronic structure have been often described in a very approximate manner.

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Speaker: Daniele Mammoli (ERC)

Title: European Research Council session

Synopsis: In this informative session, the main features of the ERC individual grants (i.e. Starting, Consolidator and Advanced Grants) will be presented, together with information on the application and evaluation process. Two former grantees will share their experiences and will provide advices on relevant aspects of the process, such as identifying a solid idea and writing a successful proposal. Finally, anybody from the audience will have the chance to ask questions to the speakers.

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Speaker: Angela Wilson

Title: Resolution-of-the-Identity and Beyond

Synopsis: Achieving quantitative accuracy in the prediction of energetic and spectroscopic properties can become challenging as the size and complexity of molecules increase due to the accompanying rise in computational costs. Developments by our group and applications that have provided insight about energetic predictions, the theoretical strategies used for the predictions and strategies for dramatically decreasing costs will be highlighted.

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Speaker: Katharine Hunt

Title: New ab initio results for interaction-induced dipoles and susceptibilities and new analytical results for transition probabilities

Synopsis: We have computed the collision-induced dipoles of H2-H and H2-H2 by finite field methods at UCCSD(T) and CCSD(T) levels, for astrophysical applications in analyzing radiative energy balances. The calculations cover 2,736 geometrical configurations of H2-H and 9,180 geometrical configurations of H2-H2. In addition to finding classical polarization effects, we have found the long-range van der Waals dispersion dipole accurately for the first time in ab initio calculations on H2-H.

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Speaker: Stuart Althorpe

Title: Real-time dynamics from imaginary-time path-integrals: theory and practice

Synopsis: We explain the theory behind path-integral real-time dynamics methods (such as CMD and RPMD), and show how this theory may be used to critique and improve such methods.

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Speaker: Florian Bischoff

Title: Explicitly Correlated Coupled-Cluster in Real Space

Synopsis: A first-quantized formulation of Coupled-Cluster is presented and used to implement Coupled-Cluster in real-space. Singularities are regularized by explicit correlation. An implementation of CC2 ground and excited states using multi-resolution analysis (MRA) in the Madness program package shows its applicability for small molecules.

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Speaker: Jacob Kongsted

Title: Polarizable Density Embedding for Proteins: Excited States in Complex Environments

Synopsis: We review recent progress within the polarizable embedding (PE) and polarizable density embedding (PDE) methods highlighting the general flexibility and accuracy of these computational models designed for calculation of general response properties of composite systems. Finally, we will show how the PDE model recently has been extended to the case of covalently bonded environments, e.g. proteins.

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Speaker: David Manolopoulos

Title: Path integral methods for reaction rates

Synopsis: I will review the RPMD rate theory approximation to adiabatic rates and the Wolynes theory approximation to non-adiabatic rates as a prelude to Joseph Lawrence's talk on how these two theories can be combined to calculate electron transfer rates over the full range of electronic coupling strengths from the adiabatic to the non-adiabatic regime.

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Speaker: Andreas Grüneis

Title: Recent progress in applying periodic coupled cluster theory to solids and surfaces

Synopsis: We will present techniques that reduce the computational cost of periodic coupled cluster theory by accelerating the convergence of calculated properties towards the complete basis set as well as the thermodynamic limit using a plane wave basis.

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Speaker: Toon Verstraelen

Title: Modeling Weak Interactions With Spherical Atomic Electron Densities

Synopsis: The Monomer Electron Density Force Field is a pairwise additive model for intermolecular interactions. The model contains only three adjustable interaction parameters, which eliminates the risk of over-fitting. MEDFF also requires precomputed fragment electron densities, which are approximated as sums of atom-centered exponential functions. Despite its low complexity, this model performs remarkably well for dispersion-dominated systems.

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Speaker: Joseph Lawrence

Title: On the calculation of quantum mechanical electron transfer rates

Synopsis: We present a simple interpolation formula for the rate of an electron transfer reaction as a function of the electronic coupling strength. The formula only requires the calculation of Fermi Golden Rule and Born-Oppenheimer rates and so can be combined with any methods that are able to calculate these rates. We show how the formula can be combined with the Wolynes theory approximation to the Golden Rule rate and the ring polymer molecular dynamics (RPMD) approximation to the Born-Openheimer rate.

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Speaker: Andreas Köhn

Title: Computing molecular properties in multireference coupled-cluster theory

Synopsis: This contribution reports on the recent progress in the computation of molecular properties in internally contracted multireference coupled-cluster theory (icMRCC). We will in particular cover the computation of hyperfine coupling tensors, non-linear response properties, and spin-orbit coupling matrix elements.

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Speaker: Denis Jacquemin

Title: Searching for Super-Accuracy in Excited State Calculations

Synopsis: This talk will be devoted to the results obtained with high-accuracy methods for the properties of electronically excited states (vertical transitions, 0-0 energies, and geometries). The consistency between the CC and sCI approaches will be shown, and benchmarks of many levels of theory, usually considered as accurate, will be discussed.

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Speaker: Jeremy Richardson

Title: Nonadiabatic quantum transition-state theory

Synopsis: We propose a new nonadiabatic quantum transition-state theory for calculating Fermi's golden-rule rates in complex multidimensional systems. This method is able to account for the nuclear quantum effects of delocalization, zero-point energy, and tunnelling in an electron-transfer reaction. We show by comparison with benchmark results on model systems that the new method avoids the problems associated with alternative approaches.

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Speaker: Aurora Clark

Title: Heavy Element Solution Chemistry – A Sojourn Through Ideal and Non-Ideal Solutions and Their Interfaces

Synopsis: This work will discuss different strategies for performing condensed phase simulations of actinides and lanthanides in solution environments that systematically approach realistic conditions associated with purification and synthesis.

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Speaker: Piotr Piecuch

Title: Toward Exact Quantum Chemistry by a Combination of Stochastic Wave Function Sampling and Deterministic Coupled-Cluster Computations

Synopsis: In this talk, we discuss a radically new way of obtaining highly accurate molecular electronic energetics, equivalent to high-level coupled-cluster calculations or to the exact, full configuration interaction, Hamiltonian diagonalization, even when many-electron correlation effects become strong. The key idea is a merger of the deterministic coupled-cluster and equation-of-motion coupled-cluster frameworks with the stochastic wave function sampling in the many-electron Hilbert space.

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Speaker: Aurelien de la Lande

Title: Toward First Principles Simulations of Biological Matter under Ionizing Radiations

Synopsis: I introduce an original set of methodologies to investigate the interaction of ionizing swift ions with biological matter and the ultrafast responses to energy deposition on the atto- to picosecond timescales. Our approach is based on a highly efficient real-time time dependent auxiliary density functional theory implementation coupled to polarizable force fields. Simulations of irradiation of DNA reveal the mecanisms of ionization and the production of low energy electrons.

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Speaker: Jochen Autschbach

Title: Chemical bonding, core spectroscopy, and magnetic properties of actinide complexes

Synopsis: We discuss first-principles calculations of magnetic resonance parameters (NMR, EPR), magnetic susceptibilities, magnetic circular dichroism, and core excitation spectra, and how the results relate to the chemical bonding involving the actinide

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Speaker: Gustavo Scuseria

Title: Quantum Chemistry for Strong Correlation

Synopsis: This lecture will address challenges and progress on the treatment of strong correlation, and its connection with quantum symmetries and degeneracy. Methods recently developed in our research group for strong correlation will be discussed.

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Speaker: Joachim Sauer

Title: Ab initio Free Energy Calculations with Chemical Accuracy for Molecule - Surface Interactions

Synopsis: We have developed and applied methodology for the quantum mechanical ab initio prediction of free energies for large periodic systems with chemical accuracy based on a QM:QM approach combining wave-function methods for the reaction site with computa¬tionally more efficient DFT calculations on the full periodic system. For efficient sampling of the anharmonic potential energy surface we solve one-dimensional Schrödinger equations for each degree of freedom separately.

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Speaker: Xiaosong Li

Title: Spin-Orbit Symmetry Breaking and Restoring in Kramers-Unrestricted Multireference Approaches

Synopsis: We present and benchmark Kramers-unrestricted relativistic two-component CASSCF and MRCI methods that include scalar relativistic effects and one-electron spin-orbit coupling during the self-consistent wave function optimization procedure. We will investigate and discuss the ability of these multireference method to restore spin-orbit symmetry in Kramers-unrestricted electronic structure framework.

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Speaker: Paola Gori-Giorgi

Title: Strong-coupling limit in DFT and Hartree-Fock: kinetic correlation energy and dispersion

Synopsis: The strong-coupling expansion of DFT provides mathematical insights on how to build approximations that can describe strong correlation. In this talk I will discuss some recent developments, particularly the extension of this limit to the case of Hartree-Fock theory and the inclusion of dispersion.

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Speaker: Chao-Ping Hsu

Title: Machine learning for electron-transfer couplings

Synopsis: Authors will share their recent findings with newly developed machine-learning based approaches for calculating electronic coupling. If time and other factors allow, she will also talk about their work on characterizing the optoelectronic properties in disordered organic materials.

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Speaker: Michal Repisky

Title: All-electron relativistic four-component Dirac–Kohn–Sham theory for solids using Gaussian-type functions

Synopsis: A major challenge in computational solid-state physics is the capability of first-principles theories to treat relativistic effects non-perturbatively when modeling material properties driven by the spin-orbit interaction. Here, we present a four-component Dirac–Kohn–Sham theory within local Gaussian-type bases for obtaining relativistic band structures of solids. Time-reversal symmetry and quaternion algebra-based formalism is introduced to reduce the computational complexity of the problem.

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Speaker: Laura Gagliardi

Title: Multireference Methods for Extended Systems

Synopsis: I will describe our latest progress in combining DMRG with pair-density functional theory (PDFT). Calculations that require active spaces larger than the feasibility limit of CASSCF will be presented. I will also report our advancements in using density matrix embedding theory in combination with localized active space self-consistent field as a solver and its application to realistic models of strongly-correlated systems.

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Speaker: Rosa Bulo

Title: Multi-scale Modeling of Chemistry in Water

Synopsis: Molecular dynamics simulations of chemical reactions in water can be significantly accelerated by a multi-scale QM/MM description of the interactions. Over the past decade several novel QM/MM models have appeared that focus specifically on reactivity in water; Constrained QM/MM models and adaptive QM/MM models. I will present our new developments on both these models, and compare the performances of the different approaches in describing nucleophilic addition reactions in water.

Abstract: download

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Poster: P1-1

Author: Rodrigo Ormazábal-Toledo

Title: Stereoelectronic control of π-nucleophilicity

Synopsis: Nucleophilicity of olefins is described in terms of the interaction between electrophile-nucleophile pair. The model successfully explains reactivity of olefins by ranking the donicity ability of the corresponding alkyl group attached to the vinyl moiety.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-2

Author: Pär Håkansson

Title: Quantum chemistry property surface and machine learning in magnetic resonance relaxation modelling

Synopsis: Interpretation of long-lived relaxation measurement are in this work addressed by means of spin-Hamiltonian trajectories. Obstacles encountered are the costly first-principles quantum-chemical calculations needed both in large numbers and depending on many spatial degrees of freedom (DOF). These obstacles are overcome by employing a machine learning approach where a classification of important DOF are done and a simplified tensor model is constructed dependent on these.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-3

Author: Kristoffer Simula

Title: Quantum Monte Carlo Simulation of Positrons in Solids

Synopsis: Positron annihilation spectroscopy is used to infer atomic and electronic structure in materials. PAS measures radiation from annihilation events of electrons and the positrons in a sample. So far theoretical predictions have been provided by density functional theory, which has it's accuracy limited to the quality of the correlation functional. To overcome DFT, we developed a quantum Monte Carlo method for positron calculations to study positron annihilation in an unprecedented accuracy.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-4

Author: Jan-Oliver Joswig

Title: Allosteric regulation of the pH-dependent Ca(II)-binding affinity in langerin

Synopsis: The dendritic receptor langerin plays an important role for the immune response of humans. Its binding affinity to a calcium(II)-cofactor is pH-dependent and sensitive for a change from 7 to 6. A histidine was identified as pH-sensor, which is interesting because there is no direct contact with the binding-site. Thus, the effect of the additional proton has to be transported via an allosteric mechanism that we aim to explain by the use of (steered)-MD and Markov state modelling.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-5

Author: Seyedeh Maryam Salehi

Title: Vibrational Spectroscopy of N$_3^-$ in the Gas and Condensed Phase

Synopsis: Azido-derivatized amino acids are potentially useful, positionally resolved spectroscopic probes for studying the structural dynamics of proteins and macromolecules in solution. This contribution presents a spectroscopically accurate model for N$_3^-$ in the gas phase and in solution and demonstrates its use in simulations of hydrated azidohomoalanine.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-6

Author: Shervin Fatehi

Title: Nonadiabatic dynamics with stochastic electronic structure forces

Synopsis: In recent years, I have been concerned with the feasibility of large-scale ab initio nonadiabatic dynamics: Can we afford to do MD? Are states ordered correctly? Can we afford inter-state couplings? Are the couplings physical? My co-workers and I have answered these questions affirmatively. I am now working to extend these successes to stochastic electronic structure techniques like full-CI quantum Monte Carlo and stochastic CC. In this poster, I will present some developments in this direction.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-7

Author: Francesco Segatta

Title: Simulation of optical-pump Xray-probe NEXAFS spectroscopy to track photo-induced dynamics of organic molecules

Synopsis: In this contribution we show how the use of time resolved optical-pump Xray-probe NEXAFS spectroscopy can be exploited to track the excited state dynamics of organic molecules. The theoretical approach for the simulation of time-resolved NEXAFS signals is introduced, and the cis-trans photo-isomerization of the azobenzene molecule is presented as a testbed case, highlighting the signatures that enable to track the system evolution from the Franck-Condon point towards the conical intersection.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-8

Author: Jakub Med

Title: Ultrafast non-adiabatic dynamics in water clusters - hydronium radical as an intermediate in the formation of hydrated electron

Synopsis: We have focused on ultrafast dynamics in water clusters early upon excitation. We have performed a series of non-adiabatic ab initio molecular dynamics calculations and here we will present the results. Two different reactive pathways take place and they are strongly affected by the initial excitation energy. Hydronium radical also plays a significant role in our observations.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-9

Author: Ondrej Gutten

Title: Metal-ligand Complex Database as a Starting Point for Development of Metal-Protein Potentials

Synopsis: A database of metal-ligand complexes that serve as models for metal-protein interactions. Structures, energies, population analysis.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-10

Author: Alireza Marefat Khah

Title: Parametrization and Evaluation of Transferable Minimal Pseudo-Potentials to Avoid Electrons Spilling-Out in Polarizable Embedded QM/MM Calculations

Synopsis: With optimized all-electron pseudo-potentials, the accuracy of calculated excitation energies at polarizable QM/MM PE-ADC(2) level improves substantially.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-11

Author: Jiří Suchan

Title: Wavelength dependent photochemistry via semiclassical dynamics

Synopsis: Theoretical treatment of photochemical reactions is typically based on semiclassical simulations, usually assuming vertical promotion of initial vibrational wavefunction. Experimentally, molecules are typically excited with a light of a well defined wavelength. In fact, photochemistry is often controlled by the wavelength. We show various applications of our new ground state nuclear density sampling method, corresponding to a constant wavelength excitation, accounting for the experimental setup.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-12

Author: Jakub Lang

Title: Beyond the LPNO-TCC: Introduction of DLPNO-TCCSD

Synopsis: Coupled cluster(CC) methods tailored by matrix product state(TCC) [1] are highly accurate post-DMRG methods, which provide an accurate treatment of non-dynamic correlation with DMRG and dynamic correlation with CC framework. While being tremendously successful, canonical TCC method cannot handle large systems. In this poster, we present a benchmark of a DLPNO-TCCSD. Tests shows that DLPNO-TCCSD provides about 99.9% the canonical energy and opens way to large scale post-DMRG calculations.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-13

Author: Jesus I. Mendieta-Moreno

Title: Observation of proton tunneling in hydrogen-bonded organic 1D molecular chains on Au(111)

Synopsis: We study self-assembled hydrogen-bonded organic 1D molecular chains in ultrahigh vacuum at 5K using combined STM and nc-AFM supported by theoretical analysis. Sub-molecular resolution hints structural information, specifically regarding the hydrogen bonds revealing proton tunneling between molecules. To study the proton transfer we use QM/MM techniques and PIMD. We observe a deep tunneling regime and a cooperative effect in the proton transfer.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-14

Author: Noelly Madeleine

Title: The Arabidopsis (ASHH2) CW domain binds monomethylated K4 of the histone H3 tail through conformational selection

Synopsis: Disorder and flexibility are prevalent both in histone tails and proteins involved in chromatin remodeling. The ASHH2 protein contains an interaction domain CW and a HKMTase domain SET. We are interested in whether CW binding is coupled to changes in structure, stability and mobility at different levels of structural organization. To explore this question, a comprehensive analysis of the ASHH2 CW:H3K4me1 complex using NMR and molecular dynamics were performed.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P1-15

Author: Yongbin Kim

Title: Effective Fragment Potentials for non-rigid fragments

Synopsis: The Effective Fragment Potential (EFP) is a first principles based model potential for the rigorous description of intermolecular interactions in condensed-phase systems. EFP decomposes non-covalent interactions into electrostatic, polarization, dispersion, and exchange-repulsion components. We developed a computational approach for the efficient utilization of EFP for flexible molecules, so-called Flexible EFP, and present extensive benchmarks of its computational efficiency and accuracy.

Room: Skarven

Abstract: download

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Poster: P1-16

Author: Yunlong Xiao

Title: The numerical instability in non-collinear DFT

Synopsis: The non-collinear spin DFT suffers from numerical instability at those points with vanishing spin. Some preliminary study on the problem is given.

Room: Skarven

Abstract: download

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Poster: P1-17

Author: Karolina Solheimslid Eikås

Title: Towards a computational protocol for VCD spectra of cyclic peptides

Synopsis: Vibrational Circular Dichroism (VCD) is a type of spectroscopy that can be used to investigate chirality and to obtain information about conformers of flexible molecules. In our work, we are developing a computational protocol that together with experiments can determine the absolute configuration of cyclic peptides. One of the problems with VCD is the sensitivity to minor structural changes and in our protocol we are testing CREST by Grimme et. al. to find the relevant conformers.

Room: Skarven

Abstract: download

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Poster: P1-18

Author: Teemu Järvinen

Title: QM/MM calculation of formic acid in argon matrix

Synopsis: We present results of QM/MM calculation of formic acid in argon matrix. Including site structure for both conformers,trans and cis, and present IR-spectrum and compare it to experimental spectrum. We also discuss how different argon-formic acid potentials affect the results and present a program that allows easy calculations of custom potentials.

Room: Skarven

Abstract: download

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Poster: P1-19

Author: Lukas Konecny

Title: Calculation of Molecular Properties Using Relativistic Real-Time TDDFT

Synopsis: The development and the scope of applications of relativistic real-time time-dependent density functional theory as implemented in quantum chemistry computer program ReSpect is presented.

Room: Skarven

Abstract: download

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Poster: P1-20

Author: Jonas Feldt

Title: Geometry Optimizations with Quantum Monte Carlo

Synopsis: Quantum Monte Carlo methods are stochastic algorithms to solve the Schrödinger equation which scale well with the system size and offer a balanced description of the ground and electronic excited states. Using both variational and diffusion Monte Carlo, we are aiming at performing efficient and accurate geometry optimizations by using different estimators for the forces with smaller statistical and systematic error based on the zero-variance zero-bias principle.

Room: Skarven

Abstract: download

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Poster: P1-21

Author: Suhwan Song

Title: Improving DFT by Quantifying Density Errors

Synopsis: Energy errors caused by exchange-correlation (XC) functional approximations can be divided as the functional error and the density-driven error. However, they require the exact XC functional and density, which make it formidable to investigate. We designed density sensitivities to quantify density errors and can be used in density-corrected DFT to greatly improve DFT results.

Room: Skarven

Abstract: download

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Poster: P1-22

Author: Mohammad Reza Karimpour

Title: Evaluating the contribution of continuum electronic states to van der Waals dispersion interactions

Synopsis: Impact of continuum electronic states on van~der~Waals dispersion interactions between atoms is discussed in this work. We evaluate this contribution for atoms modeled by simple quantum mechanical systems possessing both bound and continuum electronic states. We demonstrate that this contribution is particularly considerable for systems with weakly bound electrons.

Room: Skarven

Abstract: download

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Poster: P1-23

Author: Esko Makkonen

Title: Implementing real-time propagation time-dependent density functional theory for computing electronic circular dichroism spectra of Ag clusters

Synopsis: This poster represents a method to compute electronic circular dichroism spectrum (ECD) for large silver clusters in a framework of real-time propagation time dependent density functional theory (RT-TDDFT) with linear combination of atomic orbitals (LCAO). The implementation is done in the free GPAW software package.

Room: Skarven

Abstract: download

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Poster: P1-24

Author: Monika Dash

Title: Efficient and chemically accurate excited states with quantum Monte Carlo

Synopsis: We demonstrate an efficient protocol to compute chemically accurate ground and excited-state energies and structures with quantum Monte Carlo. Even with extremely compact wavefunctions constructed via a selected CI algorithm, we can treat multiple states in a balanced manner and compute vertical excitation energies, excited-state geometries and adiabatic excitation energies in excellent agreement with higher-level coupled-cluster values.

Room: Skarven

Abstract: download

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Poster: P1-25

Author: Klaas Gunst

Title: Advancements for the three-legged tree tensor network

Synopsis: We recently introduced The three-legged tree tensor network (T3NS). Its structure allows an efficient optimization of the wave function while enjoying more flexibility in representing entanglement than the linear matrix product state (MPS). We demonstrate our spin-adapted implementation of the T3NS. Both calculations with and without restrictions on the seniority of the wave function are presented. The problem of orbital ordering and choice of geometry is also shortly discussed.

Room: Prostneset

Abstract: download

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Poster: P1-26

Author: Ciro A. Guido

Title: Simulating advanced excitation energy loss spectroscopies of molecular excitations

Synopsis: The theoretical framework needed to describe low-loss Electron energy loss spectroscopy in a scanning transmission electron microscope is developed, in a TD-DFT framework for the description of the molecular systems. Our work paves the way to study electronic transitions in single chromophores or supramolecular aggregates and design new experiments, based on the recent introduction of a new device that allows analyzing the single components of the electron orbital angular momentum.

Room: Prostneset

Abstract: download

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Poster: P1-27

Author: Gabriel Gerez

Title: Variational and cavity-free approach to solvation in a multiresolution analysis framework

Synopsis: We have developed a Generalized Poisson Equation (GPE) solver for continuum solvation in the MRChem code. We have used multiwavelets in combination with a recent variational formalism.

Room: Prostneset

Abstract: download

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Poster: P1-28

Author: Milica Feldt

Title: Ab Initio Calculations for Spin-Gaps of Non-Heme Iron Complexes

Synopsis: We have performed an extensive computational study of the quintet-triplet gap of a series of non-heme iron-oxo species. We employed our recently proposed multireference approach CASPT2/CC to calculate the gaps and subsequently used these results to benchmark two variants of local coupled cluster approaches (DLPNO-CCSD(T) and LUCCSD(T0)). We have showed that current implementations of the local coupled cluster method are not sufficiently accurate.

Room: Prostneset

Abstract: download

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Poster: P1-29

Author: Ludovic Martin-Gondre

Title: DFT modeling of CO clathrate hydrates

Synopsis: Clathrate hydrates (gas hydrates) are nanoporous crystalline solids composed of hydrogen-bonded water molecules forming cages within which gaseous molecules are encapsulated. Carbon monoxide hydrate might be considered an important component of the carbon cycle in the solar system since CO gas is one of the predominant forms of carbon. The aim of this work is to study the structural and energetic properties of the CO hydrate using density functional theory (DFT) calculations.

Room: Prostneset

Abstract: download

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Poster: P1-30

Author: Péter Szabó

Title: Ring polymer path integrals as eigenvalue problem

Synopsis: We employed the transfer operator method for imaginary time path integrals to calculate molecular partitions functions. Due to this technique the ring polymer form the quantum partition function is transformed into an eigenvalue problem, which allows a low dimensional phase space representation of the imaginary time path integrals.

Room: Prostneset

Abstract: download

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Poster: P1-31

Author: Davide Accomasso

Title: Construction of Diabatic Electronic States of Configuration Interaction type by Localization of Molecular Orbitals with Floating Occupations

Synopsis: We present a method to contruct diabatic electronic states for systems that can be clearly separated into groups of atoms. The method is based on the localization of molecular orbitals (MO) on two or more user-defined subsystems. In such localized MO basis, the definition of diabatic states to analyze energy transfer, charge transfer or exciton coupling follows very easily.

Room: Prostneset

Abstract: download

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Poster: P1-32

Author: Johann Pototschnig

Title: Coupled Cluster for Lanthanide Monofluorides

Synopsis: In this work we are studying lanthanide monofluorides using coupled cluster computations. Effective core potentials as well as corresponding basis sets were used to describe the lanthanides and their open shells. The results will be compared to previous work and experiments.

Room: Prostneset

Abstract: download

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Poster: P1-33

Author: Moloud Kaviani

Title: Rational Design of Nanosystems for Simultaneous Drug Delivery and Photodynamic Therapy by Multiscale Modeling

Synopsis: Drug delivery systems are based on reversible interactions between carriers and drugs. Spacers are often introduced to tailor the type of interaction and to keep drugs intact. Here, we used multiscale quantum chemical calculations to model a drug delivery system based on a functionalized curved TiO2 nanoparticle of realistic size (~2.2 nm) by the neurotransmitter dopamine to carry the anticancer chemotherapeutic agent doxorubicin (DOX).

Room: Prostneset

Abstract: download

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Poster: P1-34

Author: Lincan Fang

Title: Efficient Cysteine Conformers Search by a Bayesian Optimization Method

Synopsis: We adopt a machine learning method based on Bayesian optimization combining with Density Functional Theory (DFT) to search conformers of cysteine efficiently. Comparing to the previous studies, the energy order of six low-energy conformers predicted agrees with experimental results and some new conformers have been predicted. This method can be easily extended to the conformer search of other molecules and nanostructures.

Room: Prostneset

Abstract: download

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Poster: P1-35

Author: Gianluca Levi

Title: Exploring photoinduced structural relaxation and solvation dynamics with multiscale simulations

Synopsis: This contribution highlights recent efforts towards advancing the understanding of ultrafast photoinduced processes in solution. To meet this purpose, we develop direct dynamics quantum mechanics/molecular mechanics (QM/MM) methodologies with fast and robust DFT descriptions of the excited states. We show how our tools can explain the solvent-influenced structural relaxation after light excitation in photofunctional metal complexes, helping the interpretation of time-resolved experiments.

Room: Prostneset

Abstract: download

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Poster: P1-36

Author: Petr Štěpánek

Title: Nuclear Spin-Induced Circular Dichroism: Using Nuclear Properties to Map Spatial Localization of Excited States

Synopsis: The presented work describes theoretical investigation of nuclear spin-induced circular dichroism (NSCD), one of nuclear magneto-optic effects. We studied the dependence of NSCD signal on excited states for different nuclei. The results show that a strong NSCD signal for a particular nucleus and excitation can arise only if the nucleus is a part of the excited chromophore, providing a spectroscopic tool for detection of spatial extent of excited states.

Room: Prostneset

Abstract: download

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Poster: P1-37

Author: Peter Reinholdt

Title: MFCC-PDE: Polarizable Density Embedding for large biomolecules

Synopsis: The Polarizable Density Embedding (PDE) model has been combined with the MFCC procedure. The resulting model, MFCC-PDE, allows for robust embedding calculations on larger systems, e.g., proteins. Compared to a standard Polarizable Embedding calculation, MFCC-PDE improves upon the description of short-range electrostatics and further models non-electrostatic repulsion. The method is formulated in a response theory framework, which permits calculations of a wealth of molecular properties.

Room: Prostneset

Abstract: download

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Poster: P1-38

Author: Boris Maryasin

Title: Computational Chemistry and Organic Synthesis: Let Us Build a Bridge

Synopsis: Progress in quantum chemistry and computational techniques allows chemists to understand and predict the outcome of organic reactions in a very efficient fashion. Hereby we demonstrate the power of bridging experiment and theory on some recent examples from our lab.

Room: Prostneset

Abstract: download

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Poster: P1-39

Author: Benedikt Kloss

Title: Exact quantum dynamics for electron-phonon coupled systems with multi-set matrix product states

Synopsis: We present a numerically exact method allowing to describe electron-phonon coupled quantum systems in their single-electron sector with unprecedented efficiency. The approach is based on tensor network decompositions combined with a multi-set ansatz where the wavefunction is expanded as a sum over products of electronic states and their associated vibrational wavefunctions. We apply our method to explore electron dynamics in the Holstein model in one and two spatial dimensions.

Room: Prostneset

Abstract: download

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Poster: P1-40

Author: Abhishek Khedkar

Title: Active Space Selection based on 1st order perturbation Theory (ASS1ST)

Synopsis: The choice of how many electrons and orbitals enter the active space is critical for multireference calculations and therefore an efficient and reliable active orbital space selection is crucial. In this work we propose a 'bottom-up' selection scheme based on from strongly contracted n-electron valence perturbation theory. The scheme utilizes a set of quasi-natural orbitals together with sensible thresholds. The initial application, strengths and limitations are critically discussed.

Room: Prostneset

Abstract: download

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Poster: P1-41

Author: Dmitry Makhov

Title: Ultrafast photodynamics simulations with ab initio multiple cloning approach

Synopsis: We present recent developments and applications of Ab Initio Multiple Cloning (AIMC) method for non-adiabatic molecular dynamics.

Room: Prostneset

Abstract: download

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Poster: P1-42

Author: Peter Poliak

Title: Complexes of LPMO9c from Neurospora crassa with small-molecule inhibitors

Synopsis: Lytic polysaccharide monooxygenases (LPMOs) are oxidative copper metalloenzymes with a key role in the conversion of complex biomass. We present several small inhibitors of LPMO, structures of their complexes and binding energies using DFT/B3LYP approach. Computed data correlate with experimental observations suggesting a reversible competitive inhibition mechanism. Relevant interactions between inhibitor and LPMO were identified.

Room: Prostneset

Abstract: download

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Poster: P1-43

Author: Toni Maier

Title: Relativistic 1s Core Orbital Shifts using Local Hybrid Functionals

Synopsis: In this work, we present a scalar-relativistic implementation of local hybrid functionals within the infinite-order two-component method into the RAQET program. Two-electron-relativistic effects are taken into account by a picture-change transformation of the density matrix. Furthermore, a new correction to the relativistic kinetic energy density that restores the correct iso-orbital limit will be shown. Relativistic shifts of 1s orbital energies are evaluated for several local hybrids.

Room: Importkompaniet

Abstract: download

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Poster: P1-44

Author: Fabio E. A. Albertani

Title: Composite Gaussian processes for probabilistic PES prediction

Synopsis: A composite Gaussian process regression approach is presented to predict ab initio potential energy surfaces at high levels of accuracy. We explore using large training set on HF energy and sparser training sets on the difference between the HF energy and either the deterministic or the stochastic CC energy. The ground singlet state and triplet state of H3+ are studied and the composite approach is shown to converge faster than the direct regression approach.

Room: Importkompaniet

Abstract: download

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Poster: P1-45

Author: Petra Imhof

Title: Recognition and Specificity in Base Excision Repair

Synopsis: The Base excision repair system is a machinery of enzymes, removing damages and correcting mispairs in the DNA. Glycosylases “flip” the substrate base of the DNA helix and into the active site of the enzyme and remove it base with high specificity. Recognition by human thymine DNA glycosylase is achieved at several stages: by interrogating and stabilising a partially flipped state; better acommodation of the substrate base in the active site, and in the chemical mechanism of the cleavage.

Room: Importkompaniet

Abstract: download

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Poster: P1-46

Author: Werner Dobrautz

Title: Efficient Formulation of Full Configuration Interaction Quantum Monte Carlo in a Spin Eigenbasis via the Graphical Unitary Group Approach

Synopsis: We provide a spin-adapted formulation of the Full Configuration Interaction Quantum Monte Carlo, based on the Graphical Unitary Group Approach, which enables the exploitation of SU(2) symmetry within this stochastic framework. The use of a spin-pure basis explicitly resolves the different spin-sectors and ensures that the stochastically sampled wavefunction is an eigenfunction of the total spin operator.

Room: Importkompaniet

Abstract: download

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Poster: P1-47

Author: Polydefkis Diamantis

Title: Redox-Mediated DNA Protection and Recognition of Defect Bases: Insights from Static QM Calculations and QM/MM Molecular Dynamics Simulations

Synopsis: The redox properties of native and defect DNA fragments of varying size have been investigated with static QM calculations and hybrid QM/MM MD simulations. The results for a DNA 39mer (QM/MM level) show that an 8-oxoguanine defect makes the DNA more easily oxidizable. This is in support of experimental studies suggesting that defect-induced changes in DNA redox chemistry can be exploited by the cell for the recognition of defect bases.

Room: Importkompaniet

Abstract: download

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Poster: P1-48

Author: Hiroki Uratani

Title: Divide-and-conquer DFTB-MD simulations of polaron formation process in a lead halide perovskite material

Synopsis: Polaron formation process in a lead halide perovskite material, which is of practical importance for opto-electronic devices, was simulated by molecular dynamics calculations using a linear-scaling semiempirical quantum chemical calculation method called DC-DFTB. Details of the structural deformation associated with the polaron formation will be mainly discussed, focusing on the effects of thermal motion and relaxation of the charge carriers.

Room: Importkompaniet

Abstract: download

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Poster: P1-49

Author: Sebastian Höfener

Title: Excited-state coupled-cluster frozen-density embedding for large systems

Synopsis: Combining coupled-cluster methods and density-functional theory (DFT) using frozen-density embedding (FDE) enables to study excited-state properties of chromophores with correlated wave-function methods in complex environments as routine applications.

Room: Importkompaniet

Abstract: download

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Poster: P1-50

Author: Henning Henschel

Title: Rates of Proton Transfer in Water from Semi-Empirical QM/MM Simulations

Synopsis: Our aim is to understand the molecular processes behind a number of relaxation processes relevant for MRI measurements. For this we are planning simulations of the proton transfer between biomolecular fragments and water. We have now tested a series of semi-empirical methods for their ability to correctly describe proton transfer in water. QM/MM simulations of an excess proton in a droplet model returned proton transfer rates close to the experimental value for several of the tested methods.

Room: Importkompaniet

Abstract: download

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Poster: P1-51

Author: Zack Williams

Title: Density functional correlation theories based on the Unsöld approximation

Synopsis: Unsöld-W12 (UW12) is an approximate method for including explicit correlation in density functional theory. The approximation has a similar form to MP2, without the dependence on virtual orbitals. Therefore, unlike double hybrid functionals, the approximation does not suffer from poor basis set convergence and is fully self-consistent.

Room: Importkompaniet

Abstract: download

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Poster: P1-52

Author: Souloke Sen

Title: Multiscale modelling of environmental effects on the absorption energy of chlorophyll in LHC II complex in plants

Synopsis: A multiscale modelling of the environmental effects on the absorption energy of a chlorophyll a in a previously proposed quenching site of a LHC II complex.

Room: Importkompaniet

Abstract: download

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Poster: P1-53

Author: Perttu Lantto

Title: Quantum Dynamical Effects on 3He NMR in Endohedral Fullerenes

Synopsis: Experimentally observed monomer-dimer 3He NMR shifts in fullerenes are studied with path-integral Monte Carlo (PIMC) simulations using pre-parameterized potential energy and NMR surfaces. We expose the role of quantum dynamics of the nuclei on 3He NMR shifts at different temperatures and show that this information could be used to investigate negative thermal expansion of Buckminster fullerene.

Room: Importkompaniet

Abstract: download

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Poster: P1-54

Author: Agnieszka Dybala-Defratyka

Title: Effect of Solvation on Kinetic Isotope Effects on Hydrogen Abstraction from Ethanol in Aqueous Solution

Synopsis: Hydrogen abstraction from ethanol by atomic hydrogen in aqueous solution is studied using two theoretical approaches; multi-path variational transition state theory and a path integral formalism in a combination with free-energy perturbation and umbrella sampling. Performance of models is compared to the exp values of H kinetic isotope effects. The effect of the transition state conformation and the position of water molecules interacting with the solute on the isotope effects are discussed.

Room: Importkompaniet

Abstract: download

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Poster: P1-55

Author: Andrew Molino

Title: Theoretical Insights to Novel Beryllium Reactivity

Synopsis: We report results of theoretical investigations for a series of novel beryllium carbodicarbenes (CDC) in collaboration with synthetic studies. We have utilized Atoms in Molecules (AIM) calculations and Energy Decomposition Analysis (EDA) to determine the local electronic environment. Further we have undertaken mechanistic studies to understand different reactivity.

Room: Importkompaniet

Abstract: download

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Poster: P1-56

Author: Jin Wen

Title: Search for Optimal Arrangements of Perylene Pairs in Singlet Fission

Synopsis: A simple model described by the diabatic frontier orbitals is applied in searching for the local maximum rate of singlet fission (SF). First, we examine the value of the square of the electronic matrix element in six-dimensional space. Then, the SF rates in the local maxima of molecular pairs were obtained with the approximation of the Marcus theory. These optimized geometries would provide a guideline for crystal engineering or covalent dimer synthesis in SF materials.

Room: Importkompaniet

Abstract: download

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Poster: P1-57

Author: Giovanni Scalmani

Title: Exploring the Combination of Linear Response and State Specific Approaches for a More Accurate Description of Excited States in Solution

Synopsis: The combination of TD-DFT and PCM provides an accurate picture of excited states in solution, but it is deceivingly straightforward. Either the linear response or a state specific approach is used, but each provides a partial picture of the physical phenomenon. We present an implementation of a method that combines these two approaches in an effective way, with user defined weights, and with the goal of providing the best description of each electronic transition based on its characteristics.

Room: Importkompaniet

Abstract: download

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Poster: P1-58

Author: Christopher Ehlert

Title: Iron Doped Gold Cluster Nanomagnets: Ab Initio Determination of Barriers for Demagnetization

Synopsis: Magnetic properties of small- and nano-sized iron doped gold clusters are calculated at the level of second order multireference perturbation theory. The approach is first tested for small even and odd electron count systems. We then apply this methodology to the tetrahedral and truncated pyramidal nano-sized iron-doped gold clusters. The resulting magnetic properties dependent on the substitution scheme and some nanoclusters exhibit single molecule magnet characteristics.

Room: Importkompaniet

Abstract: download

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Poster: P1-59

Author: Raz Benson

Title: Which quantum statistics–classical dynamics method is best for water?

Synopsis: We make a systematic comparison of a range of methods for combining quantum statistics with classical molecular dynamics, to account for nuclear quantum effects in the infrared spectrum of water. We focus especially on the prediction of overtone and combination bands, the intensities of which are underestimated by path-integral methods like CMD and TRPMD. These features are more accurately captured by the linearised semi-classical initial value representation.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-60

Author: Deping Hu

Title: Inclusion of Machine Learning Kernel Ridge Regression Potential Energy Surfaces in On-the-Fly Nonadiabatic Molecular Dynamics Simulation

Synopsis: Machine learning potential energy surfaces (ML-PESs) are constructed and then used in the nonadiabatic dynamics simulation. The dynamics results based on ML-PESs are consistent with those based on CASSCF PESs, and are more efficient.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-61

Author: Toomas Tamm

Title: Linearization of Moment Tensor Potentials

Synopsis: Moment Tensor Potentials (MTP) are a method of approximation of molecular potential energy surfaces, with application in machine learning models. We propose an alternative relaxed formulation of the original potential energy function where parameter optimization is expressed as a linear sparse approximation problem. The models provide approximations with a RMSE of 0.0393 kcal/mol for the water dimer and 0.1179 kcal/mol for the trimer, relative to CCSD(T) data.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-62

Author: Jacopo Fregoni

Title: Strong light-molecule coupling can enhance the photoisomerization quantum yield.

Synopsis: The strong coupling between molecules and photons in resonant cavities offers a toolbox of new effects to manipulate photochemical reactions. In this regime, the molecular degrees of freedom mix with the resonant cavity photons, yielding hybrid light-matter states: polaritons. Here we discuss the conditions to selectively enhance/quench the quantum yields of a reversible photoisomerization through strong coupling, simulating such process by reproducing a realistic experimental setup.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-63

Author: Attila Tajti

Title: Accuracy of Excited State Spin-Component-Scaled CC2 potential energy surfaces

Synopsis: The spin-component-scaled CC2 variants SCS-CC2 and SOS-CC2 methods are benchmarked for electronically excited valence and Rydberg states of small and medium-sized molecules. Results show that both serious flaws of CC2 identified in earlier studies – underestimation of Rydberg states and inaccurate potential energy surfaces - are largely remedied by spin-component scaling.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-64

Author: Kyoung Koo Baeck

Title: Dissociative electron attachment to SF5CF3 leading to a stable combination of anionic SF4 and neutral CF4: Ab initio molecular dynamics study

Synopsis: Among the possible removal processes of the greenhouse compound, SF5CF3, its reaction with low-energy electrons is the most probable pathway, and several researches have confirmed the production of the anionic product (SF5ˉ) and radical (CF3). The energy of the product combination, however, is not stable enough to be an ultimately stable stage. We found an additional pathway leading to the more stable combination of anionic SF4 and neutral CF4 by the recombination of the initial fragments.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-65

Author: Dustin Kaiser

Title: Computational modelling of the ionization of organic biradicals

Synopsis: We use high-level computational approaches to investigate the spectroscopy of the organic biradicals ortho-benzyne and pentadiynylidene. Comparison with experimental data obtained from mass-selective threshold photoelectron spectroscopy highlights the varying goodness of different quantum-chemical approaches. For both systems, more approximative methods can be seen to fail even in the qualitatively correct prediction of the systems' structures.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-66

Author: Mirza Wasif Baig

Title: Theoretical investigation of effect of alkylation and bromination on spin-orbit couplings in BODIPY based photosensitizers

Synopsis: BODIPY’s with halogen atoms are found to have SOCs significantly greater than BODIPY’s possessing just alkyl moieties. Excited state dynamics of brominated-BODIPY was further explored with TD-DFT surface hopping molecular dynamics on potential energy surfaces resulting from the eigenstates of the total electronic Hamiltonian including the spin-orbit (SO) coupling.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-67

Author: Nahoko Kuroki

Title: Is it possible to predict supercritical properties by ab initio molecular dynamics simulation?: Effective Fragment Potential version 2‐Molecular Dynamics (EFP2-MD) simulation study

Synopsis: Predicting supercritical properties by EFP2-MD.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-68

Author: Patrick Schneider

Title: Molecular Vibrational Frequencies and the Diagonal Born-Oppenheimer Correction within the Nuclear-Electronic Orbital Framework

Synopsis: The nuclear-electronic orbital (NEO) method treats select nuclei, typically protons, quantum mechanically on the same level as the electron. To compute molecular vibrational frequencies within the NEO framework, an extended Hessian that depends on coordinates of both the classical nuclei and the quantum nuclei expectation values is diagonalized. Diagonal Born-Oppenheimer corrections to the NEO potential energy surface do not significantly impact the bond lengths and vibrational frequencies.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-69

Author: Cecilia Chávez-García

Title: Funnel metadynamics on the Kelch domain of Keap1.

Synopsis: Funnel metadynamics is a method that allows a ligand to enhance the sampling of the target binding sites and its solvated states. In this method, a funnel-shaped potential is applied to the system, reducing the space to explore in the unbound state and allowing an accurate estimation of the binding free-energy surface. In this work, we performed funnel metadynamics on a DLGex peptide and the Kelch domain of Keap1. The peptide contains the "DLG" motif necessary in Neh2 for Kelch binding.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-70

Author: Michael Andree Heuer

Title: |Ψ|² Analysis: Electronic Motifs and Energy Partitioning with Quantum Monte Carlo

Synopsis: Weighted maxima of |Ψ|² can be obtained with quantum Monte Carlo methods. These maxima define basins of attraction providing a natural partitioning of ℝ³ᴺ and exhibit transferable and recurrent motifs of spin-correlated electron positions. Thus, energy can be partitioned into contributions from every maximum and the motifs therein.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-71

Author: Ayako Nakata

Title: Atomic and electronic structure analysis of Pd@Ag core-shell nanoparticles by large-scale DFT calculations

Synopsis: We have introduced multi-site support functions (MSSFs), which are the linear combinations of atomic orbital basis functions on a target atom and its neighbor atoms, to reduce the computational cost without losing accuracy. By using the MSSFs, we investigate the site- and size-dependence of the atomic and electronic structures of Pd@Ag core-shell nanoparticle catalysts. We report the electronic structure dependence of Pd@Ag on the Ag-shell thickness.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-72

Author: Andrea Hamza

Title: Theoretical Challenges of Enantioselectivity in Asymmetric Hydrogenation of Benzofurans Catalyzed by a Bulky Ruthenium-NHC complex

Synopsis: Despite of the extensive structural investigations performed for the hydrogenation of 2-methylbenzofuran with a highly versatile chiral ruthenium-NHC catalyst, the mode of action of the catalyst still remains unexplored for aromatic systems. The aim of our theoretical study was to gain a better insight into the structure of the active catalyst as well as, to elaborate and understand the reaction mechanism for such systems.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-73

Author: Aurora Ponzi

Title: Multi-slit-type interference in C 2s photoionization of polyatomic molecules

Synopsis: We have explored the feasibility of examining interference in photoemission from C 2s-derived orbitals in simple hydrocarbon molecules. This permitted us to verify the existence of oscillations in interference profiles which depend on the internuclear distance, on the electronic structure and on the orbital composition.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-74

Author: Veronika Juraskova

Title: Exploiting artificial neural networks in simulation of complex ionic chemical environment

Synopsis: In the present study, we apply the artificial neural networks (ANN) in the MD simulation of catalytic chemical process in the condensed phase. The ANN are trained using PBE and PBE0 energies and forces to obtain accurate description of the ion-solvent interactions and reaction barriers. We combine the ANN with state-of-the-art algorithms (e.g. multiple time-stepping) to facilitate the sampling of complex potential energy surface and achieve sufficiently long simulations at reduced cost.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P1-75

Author: Thomas Heine

Title: Fragment-Based Restricted-Active-Space Configuration Interaction with Second-order Correction Embedding for Periodic Hartree-Fock Wave Function

Synopsis: We present an embedding method for restricted-active-space configuration interaction with second-order perturbative correction (RASCI-PT2) embedded in the periodic Hartree-Fock (HF) wave function. The method allows us to calculate the electronic structure (ground and excited states) of localized feature for fragments in periodic systems.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-76

Author: Jiri Pittner

Title: Combining DMRG and coupled cluster approaches for static and dynamic correlation

Synopsis: We have extended the tailored-CC idea to the Hilbert-space multireference CC, where a small CAS1 space contains these most strongly contributing determinants, while a relatively large CAS2 space is treated at the DMRG level. We also suggest an intertwined iterative combination of DMRG and CC, where DMRG represents the first iteration, tailored CC the second one, and DMRG with a similiraty-transformed Hamiltonian the third one. We present first numerical results of testing these approaches.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-77

Author: Thomas Dresselhaus

Title: Time-Dependent Linear Response for Coupled Electron-Boson Systems

Synopsis: Time-dependent linear response theory is the most widely used approach for calculating excitation energies of electronic systems. In doing so, the Casida equation is solved. This formalism is not restricted to electronic systems, but can also be applied to systems coupled to other (quasi-)particles, such as protons, photons, Drude oscillators, or nuclear vibrations. On the poster, theoretical aspects, details of a general implementation and sample applications will be shown.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-78

Author: Robert Shaw

Title: Accelerating high-accuracy electronic structure theory

Synopsis: We present a linear-scaling, high-accuracy method for computing interaction energies in large chemical systems.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-79

Author: Johannes Dietschreit

Title: Insights into Chemistry through the Computation of Free Energy Hot-Spots

Synopsis: We present a method for visualising and localising free energy differences. It calculates the vibrational free energy part and locates changes in the potential energy surface. These hot-spots are interpreted as the locations causing the overall free energy to change. The performance of our method is illustrated for two examples: The binding of an inhibitor to a protein using classical mechanics, and the identification of those atoms affected by the anomeric effect using quantum mechanics.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-80

Author: R. K. Kathir

Title: Non-orthogonal configuration interaction to study singlet fission

Synopsis: We have developed a variation of the non-orthogonal configuration interaction approach to study the interaction between excited states on neighbouring molecules in a cluster. We have significantly reduced the computational bottlenecks that arise due to the use of non-orthogonal orbitals. We present the results of our method applied to study energy transfer in singlet fission, an efficient multiple exciton generation process in organic semiconductors.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-81

Author: Jonathan Tennyson

Title: Ultra low energy scattering and chemistry with the R-matrix

Synopsis: New developments in experimental methods allow for the routine production of ultracold (microkelvin) atoms and molecules. Wo report on the development of a new program, RmatReact, which uses the R-matrix and associated methodology to accurately simulate heavy particle collision events at these ultracold temperatures.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-82

Author: Hugh G. A. Burton

Title: Non-Hermitian Quantum Chemistry: Connecting Excited States through the Complex Plane

Synopsis: We present an entirely novel approach for exploring electronic excited stationary states that exploits the properties of non-Hermitian Hamiltonians. For example, by performing a complex analytic continuation of the electron-electron interaction in Hartree–Fock theory, we expose a hidden connectivity of multiple stationary states across the complex plane. We demonstrate how this allows a ground state to be naturally evolved into an excited by following a well-defined complex adiabatic connection.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-83

Author: Tapio Rantala

Title: Real-time response from imaginary-time simulation: Hacking quantum statistics with path-integral Monte Carlo

Synopsis: Electric field response is a fundamental property of matter. It appears as different types of polarizabilities. Static and dynamic multipole polarizabilities are the origin of optical properties and phenomena. We introduce PIMC approach for evaluation of polarizabilities at finite temperature, with all degrees of freedom of quantum statistical physics. Electron–nuclei nonadiabatic effects and electronic correlations are included exactly. We give benchmark results for small atoms and molecules.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-84

Author: Qin Yang

Title: Probing chiral properties of medium-to-large organic molecules: The VPT2 approach

Synopsis: Chiral spectroscopies are powerful tools to investigate the biological activity of molecules. Due to their sensitivity, accurate simulations are necessary to support experiment. Thanks to recent advances, this can be achieved by proper inclusion of anharmonic effects. However, available anharmonic models require some careful parametrization, which make them unpractical for larger molecular systems. This contribution will illustrate such challenges and explore paths to overcome this issue.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-85

Author: Raja Mani Kandan Vanniyaperumal Baskaran

Title: Thermochemistry and electronic structure properties of cyclacenes using homodesmotic reactions and DFT

Synopsis: Belt shaped molecules consisting of fused conjugated hydrocarbons are potential nanostructures due to their radially oriented p orbitals and superior optoelectronic properties. [m] Cyclacenes are one such set of molecules formed by fusing m membered conjugate rings. In this work we studied and compared the thermochemistry and the electronic structure properties of different cyclacenes formed from benzene, cyclobutadiene and cyclooctatetraene using homodesmotic reactions and DFT.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-86

Author: J. Emiliano Deustua

Title: Accurate Electronic Energies by Stochastic Wave Function Sampling and Deterministic Coupled-Cluster and Equation-of-Motion Coupled-Cluster Computations

Synopsis: In this presentation, we discuss our recent progress in the area of merging deterministic coupled-cluster and stochastic configuration interaction and coupled-cluster Quantum Monte Carlo frameworks. This includes the extension of the previous ground-state work to excited states and the direct recovery of the exact, full configuration interaction, energetics in weakly and strongly correlated systems via cluster analysis of wave functions resulting from Quantum Monte Carlo propagations.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-87

Author: Marius Kadek

Title: All-electron relativistic four-component Dirac-Kohn-Sham theory for solids using Gaussian-type functions

Synopsis: To address the challenge of reliable and efficient first-principles modeling of relativistic effects in spin-orbit-coupled solids containing heavy elements, we formulated and developed a four-component all-electron theory for periodic systems solving the Dirac-Kohn-Sham equation within local Gaussian-type bases.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-88

Author: Ravi Tripathi

Title: Unraveling Proton Storage Site and Generic Proton Release Pathway in a Prototype Light-Driven Proton Pump Bacteriorhodopsin

Synopsis: I will present the results of our recent work on bacteriorhodopsin protein where we disclose the precise location and chemical identity of the proton storage group that remains a topic of debate for many years in addition to discovering the subsequent proton release pathways by which the stored proton can finally translocated via a Grotthuss-type proton migration mechanism toward the exit channel into the aqueous solution.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-89

Author: Gang Lu

Title: Unraveling Exciton Dynamics in 2D Van der Waals Heterostructures

Synopsis: First-principles method is developed to unravel exciton dynamics in 2D van der Waals heterostructures.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-90

Author: Andreas Hansen

Title: Structure Optimisation of Large Transition Metal Complexes with Extended Tight-Binding Methods

Synopsis: We report on the capability of the GFNn-xTB[1,2] methods to perform fast and accurate full quantum mechanical geometry optimisations of large transition metal complexes and supramolecular organometallic structures.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-91

Author: Henrik R. Larsson

Title: Combining the Density Matrix Renormalization Group with Selected Configuration Interaction

Synopsis: We combine selected configuration interaction (SCI) techniques with the Density Matrix Renormalization Group (DMRG).

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-92

Author: Dennis Dinu

Title: On the Synergy of Matrix-Isolation Infrared Spectroscopy and Vibrational Configuration Interaction Computations

Synopsis: Based on the one-hand combination of Matrix-Isolation Infrared Spectroscopy and Vibrational Configuration Interaction Calculations, we establish an iterative strategy to spectroscopically identify and characterize molecules by their vibrational structure. For instance, this synergy of experiment and theory enables us to add new insights on the rotational-vibrational spectrum of water monomers captured in neon and argon matrices.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-93

Author: Tomislav Begusic

Title: Single-Hessian thawed Gaussian approximation: The missing rung on the ladder

Synopsis: To alleviate the computational cost associated with on-the-fly ab initio semiclassical calculations of vibrationally resolved electronic spectra, we propose the single-Hessian thawed Gaussian approximation, in which the Hessian of the potential energy at all points along an anharmonic classical trajectory is approximated by a constant matrix. The single-Hessian version performs as well as the more expensive thawed Gaussian approximation and significantly better than the global harmonic schemes.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-94

Author: Maricris Mayes

Title: A Theoretical Study on the Gas- and Aqueous-Phase Photodegradation and Thermal Decomposition Channels of Pyruvic Acid

Synopsis: Pyruvic acid (PA) is a key intermediate in the keto-acid chemistry of atmospheric aerosols. In this work, several pathways, both in gas and aqueous phase, leading to to vinyl alcohol, acetaldehyde, and acetic acid were explored. All the pathways favor decomposition in solvation except for the acetaldehyde pathways. Moreover, using the TDDFT, only the hydroxycarbene channel allows photodegradation to proceed within the 300-380 nm through the first triplet and singlet excited states.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-95

Author: Jasmina Sabolović

Title: DFT-calculated Magnetic Parameters of Physiological Copper(II) Complexes with L-asparagine and L-histidine: A Tool for Verification of Predicted Lower-energy Conformers in Aqueous Solution

Synopsis: The magnetic parameters of the low-energy aqueous conformers of bis(L-asparaginato)copper(II) and (L-histidinato)(L-asparaginato)copper(II) with various in-plane and apical donor atoms were computed by Density Functional Theory (DFT). In a quantitative comparison to experimental electron paramagnetic resonance data measured in aqueous solutions, we found a perfect agreement of the hyperfine coupling constants for conformers with an apical oxygen atom (intramolecular or from a water molecule).

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-96

Author: Roberto Di Remigio

Title: Diagrammatic Coupled Cluster Monte Carlo

Synopsis: We present the diagrammatic coupled cluster Monte Carlo algorithm that solves the linked equations of coupled cluster theory. We sample the connected expansion of the similarity-transformed Hamiltonian generating coupled cluster diagrams on the fly. This affords a representation of noninteracting systems with a constant memory cost and reduced CPU cost. The algorithm can leverage locality without additional assumptions.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-97

Author: Arno Förster

Title: A Subquadratic, Pair Atomic Resolution of the Identity-Based SOS-AO-MP2 Implementation in ADF

Synopsis: We present a production level implementation of pair atomic resolution of the identity (PARI) based MP2 in the Slater type orbital (STO) based Amsterdam Density Functional (ADF) code. Furthermore, we describe a subquadratically scaling, atomic orbital based spin-opposite-scaled (SOS) MP2 approach with an exceptionally small prefactor. The low cost of our method allows for the evaluation of the post-SCF energy correction to the price of a few SCF cycles.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-98

Author: Yuki Oba

Title: A path integral molecular dynamics study of muoniated acetone radicals

Synopsis: The on-the-fly ab initio density functional path integral molecular dynamics (PIMD) simulations, which can account for both the nuclear quantum effect and thermal effect, were carried out to evaluate the structures and “reduced” isotropic hyperfine coupling constants (HFCCs) for muoniated and hydrogenated acetone radicals (2-muoxy-2-propyl and 2-hydoxy-2-propyl) in vacuo. We will propose a new solvation model, STED model, which can include electron spin transferring effect between a solute.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-99

Author: Thitiya Boonma

Title: Molecular dynamics simulation study of the drug resistance mechanism of hepatitis C virus NS3/4A to Paritaprevir due to D168N/Y mutations

Synopsis: Molecular dynamics simulation study of the drug resistance mechanism of hepatitis C virus NS3/4A to Paritaprevir due to D168N/Y mutations.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-100

Author: John Herbert

Title: New Developments in Fragment-Based Quantum Chemistry

Synopsis: Several fragment-based approaches to quantum chemistry are described. One is an "extended" version of symmetry-adapted perturbation theory (XSAPT) that accounts for both many-body polarization and nonadditive dispersion effects. Another is a variational formulation of the generalized many-body expansion that provides a very general framework for fragment-based calculations at any level of theory, with straightforward analytic gradients.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-101

Author: Michal Przybytek

Title: Dispersion Energy of Symmetry-Adapted Perturbation Theory from the Explicitly Correlated F12 Approach

Synopsis: Methods of the explicitly correlated F12 approach are applied to the problem of calculating the uncoupled second-order dispersion energy. With Slater-type correlation factor, it is possible to recover the dispersion energy with average relative errors consistently smaller than 0.1% using basis sets of triple-zeta quality.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-102

Author: Pier Paolo Poier

Title: Non-variational induced Multipoles for Polarizable Force Fields: Theory and Implementation for Molecular Dynamics Simulations

Synopsis: We present a Lagrange formalism which allows the use of non-variational induced multipoles in polarizable Force Fields. The theory is tested and implemented for Molecular Dynamics simulations with periodic boundary conditions for the recently proposed Bond Capacity model which introduces polarization at the charge-level.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-103

Author: Michał Jaszuński

Title: Relativistic four-component study of through-space spin-spin coupling constants

Synopsis: Four-component approach at the density functional level of theory is used to study and visualize through-space NMR spin-spin coupling constants (SSCC). The values of SSCCs of the type Se-Se, Se-Te and Te-Te in three similar molecules determined in the relativistic and nonrelativistic approach are compared. We discuss the first-order current densities induced by the nuclear magnetic dipoles, and different possibilities to visualize the relativistic effects are considered.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-104

Author: Maikel Ballester

Title: Potential energy Surface for the ground electronic state of SSiH

Synopsis: This work presents an analytical function for the potential energy surface (PES) of the SSiH. The PES is constructed in the frame of the many-body expansion (MBE) formalism. Multi-reference configuration interaction with Davidson corrections ab initio energies, were used for the fit. Dunning basis sets AVTdZ and AVQdZ were used together with a three parameter scheme to extrapolate to the complete basis set limit. Topological features and exploratory dynamics calculations are discussed.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-105

Author: Keiran Rowell

Title: Structure Activity Relationships for Carbonyl Photolysis

Synopsis: The photolysis reactions of 20 structurally diverse carbonyls are calculated on all relevant electronic states (S1, T1, S0) to elucidate relationships between a carbonyl’s structure and its photochemistry. The Norrish Type I & II, and all major ground-state reactions are surveyed. These structure-photolysis relationships could extend atmospheric chemistry models, which currently neglect many structural effects, due to experimental rate data being limited to a few prototypical carbonyl species.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-106

Author: Adrià Gil

Title: Using DFT and Semi-Empirical Methods as Alternative to QM/MM Approach to Study Biological Systems: Interaction between Metal Complexes Containing Phenanthroline Derivatives and DNA Duplex and G-quadruplexes

Synopsis: We propose DFT and semi-empirical methods as alternatives to the most popular QM/MM approach for the treatment of biochemical systems. Such systems consist on a metal complex containing phenanthroline interacting with DNA duplex (~500 atoms) and G-quadruplexes (~1000 atoms). The complete DFT treatment by using SIESTA software gives excellent results at reasonable computing time for these large biological systems. PM6-DH2 and PM7 semi-empirical methods give also very good results for geometries.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-107

Author: Ryo Nagai

Title: Machine Learning Kohn-Sham Density Functionals from Molecules

Synopsis: We develop a systematic machine-learning scheme to improve the density functional in Kohn-Sham DFT, by representing the functional form with a flexible neutral network (NN) and training it to reproduce accurate properties of a few molecules. Just with the small training data, our functionals show comparable accuracies to existing ones for hundreds of molecules. Also, our method has successfully increased non-locality of a functional by adding nodes, resulting in the improvement of accuracy.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-108

Author: Marta Rosa

Title: Extension of the Optimal Control Theory to Solvated Systems

Synopsis: We extended optimal control theory for molecules subject to laser pulses to the case of solvated systems. Electronic and optical properties of a molecule in a solvent can differ substantially from the ones in vacuo, as its electonic dynamics is coupled with the dynamics of the environment. The solvent was treated with the Polarizable Continuum Model, which provides a reliable description of the solvent dielectric properties, including the additional terms explicitly in the system Hamiltonian.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-109

Author: Adam Baskerville

Title: Calculating high precision, two-electron correlation data

Synopsis: In this poster we show the use of Ball Arithmetic and DoubleDouble/QuadDouble data types in quantum chemistry. It will be shown that Ball Arithmetic can provide rigorous error bounds for two-electron integrals and Hartree Fock energies. We also show that DoubleDouble and QuadDouble data types offer a substantial computational advantage over MPFR types in high precision fully-correlated calculations. High accuracy two-electron correlation data using these techniques will be presented.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-110

Author: Zahra Jamshidi

Title: Charge-Transfer Surface Enhanced Resonance Raman: Effective Factor in Understanding the Selection-rules

Synopsis: Surface-enhanced resonance Raman (SERS) is a powerful technique for ultrasensitive analysis and single-molecule detection. Since the discovery of SERS, elucidating the origin and selection rules of peak enhancements are the challenging and controversial process.1 Different experimental and theoretical groups have tried to propose the unified model for variation of signal based on the two main mechanisms, electromagnetic (EM) and charge-transfer (CT) chemical. 2 The charge-transfer mechanism is a

Room: Arbeidskontoret-1+2

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Poster: P1-111

Author: Sergey Akimenko

Title: A unified lattice model and modern statistical methods implemented in Surface Science Modeling and Simulation Toolkit

Synopsis: To simulate complex adsorption systems, we propose the Surface Science Modeling and Simulation Toolkit (SuSMoST). It includes a number of utilities and implementations of statistical physics algorithms. SuSMOST automatically builds formal graph and tensor-network models from atomic description of adsorption complexes. With methods of various nature it generates representative samples of adsorption layers and computes its thermodynamic quantities.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-112

Author: Cristian Celis-Barros

Title: Theoretical Examination of Covalency in Berkelium(IV) Carbonate Complexes

Synopsis: Covalency in actinides is still not well understood with most of the literature supporting an orbital energy-match covalency mechanism for the later actinide complexes. Herein, we prove the possibility of enhancement of covalency by orbital-overlap in Bk(IV) under carbonate and hydroxyl-carbonate environments.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-113

Author: Przemyslaw Dopieralski

Title: Towards the H/D isotope effect. Size of benzene vs perdeuterated benzene.

Synopsis: For crystalline systems isotope effect is manifested through different temperature expansion of unit cell volume of crystals containing distinct isotopes of the same element. We propose procedure to determine the effective „atomic size”, based on ab initio trajectories computed with different target temperatures – thus problem is reduced to determination of volume inside which atom (atomic nucleus) can be find with suitably high probability.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-114

Author: Vitaly Gorbunov

Title: Grand canonical Monte Carlo simulation of Fe-terephtalate ordering on Cu(100)

Synopsis: We report a detailed lattice model of terephthalic acid (TPA) and iron ordering on Cu (100) surface taking into account multiple interactions in the adlayer: carboxylate-Fe coordination, hydrogen bonding and surface mediated interactions. We have calculated the phase diagram of the adlayer. It is revealed that long-range interactions between Fe-Fe and TPA-Fe are needed to reproduce most of the structures found experimentally.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-115

Author: Martin Breza

Title: On Camptothecin Aggregation in DMSO and Aqueous Solutions

Synopsis: Optimized structures and TD-B3LYP transitions of camptothecine lactone head-to-tail π-aggregates in syn and anti conformations up to tetramers in DMSO and aqueous solutions are compared using B3LYP with D2 dispersion correction and ωB97XD functionals, cc-pVDZ basis sets and the IEFPCM approximation of solvent effects.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-116

Author: Magda Pascual-Borràs

Title: Understanding the aqueous speciation of molecular metal oxides

Synopsis: The information about reaction pathways in polyoxometalate (POM) ions is needed to understand the degradation of catalysts and the structural evolutions among different POMs. Moreover, the formation mechanisms of Ta and Nb POMs are not understood. In that sense, we have used Density Functional Theory (DFT) to rationalize the observed species in solution and develop an understanding of polyoxoniobates aqueous speciation.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-117

Author: Dmitry Bezrukov

Title: Theoretical view on atomic mobility in rare gas matrices

Synopsis: This work is devoted to modeling the mobility of H and O atoms in Ar, Kr and Xe matrices. A multiscale model based on ab initio calculations of diatomic molecules, diatomic-in-molecule approach to determine the equilibrium geometry of matrix-isolated atoms and thermodynamic analysis to find stable capture sites was proposed. The obtained values of activating barriers allow to explain the experimental data on the existence of several temperature mobility activating thresholds.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-118

Author: Callum Bungey

Title: Non-Born-Oppenheimer Electronic-Vibrational Structure Applied to Vibronic Spectra Prediction

Synopsis: The breakdown of the Born-Oppenheimer approximation occurs in many chemically important circumstances. By approximating vibrations harmonically with linear vibronational coupling we can treat all degrees of freedom quantum mechanically and simultaneously to predict vibronic spectra using time-dependent mean-field. This lays the bedrock for correlated methods for combined electronic-nuclear dynamics based on the electronic coupled cluster method.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-119

Author: Lluis Artus

Title: Rational co-catalyst design for amide hydrogenolysis based on DFT calculations.

Synopsis: The mechanism for amide hydrogenolysis catalyzed by a Noyori iron catalyst and a secondary amide co-catalyst was computationally studied in our group by using DFT methods. A microkinetic model was build after identifying the role of the co-catalyst as a proton shuttle in the rate limiting step and catalyst poisoning. It allowed us to identify promising co-catalyst candidates which were tested afterwards in the lab and showed good agreement with the computational predictions

Room: Arbeidskontoret-1+2

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Poster: P1-120

Author: Ganna Grynova

Title: Topology-Driven Molecular Electronics Lacking π-Conjugation

Synopsis: Is π-conjugation necessary to achieve efficient transport in molecular electronics? In this work we put forward an alternative strategy for modulating the transport in unimolecular electronics that is based on molecular topology and succeeds even in systems completely lacking π-conjugation, e.g., carbon nanothreads, diamondoids and graphane derivatives.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-121

Author: Gavin Huang

Title: Without Compromising Efficiency and Accuracy: Solving the Nuclear Schrödinger Equation using Path Integral Monte Carlo Simulation with Modified Shepard Interpolation

Synopsis: The convergence efficiency in path integral methods can be improved by using high order action formalisms. Here we compare the standard approximation to the action and three high order schemes, the resulting PIMC methods are applied to two realistic potential energy surfaces, for H2O and HCN-HNC. For systems beyond four atoms, we intend to demonstrate that by combining modified Shepard interpolation method with PIMC, we are able to accurately calculate the Hamiltonian.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-122

Author: Tomoharu Isobe

Title: GW(Γ) calculation for photoabsorption energies of spin polarized systems

Synopsis: The one-shot GW method beginning with the local density approximation enables one to calculate photoemission and inverse photoemission spectra. In order to calculate photoabsorption energies (PAEs), one had to additionally solve the Bethe–Salpeter equation. We developed a new GW method to calculate PAEs without solving the BSE. We applied he self-consistent LGWΓ method to our method, and found that hat this method gives the PAEs within 0.1 eV accuracy.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-123

Author: Stefano Pieraccini

Title: Accelerated molecular dynamics simulation of glutamine recognition and binding by γ-glutamyltransferase.

Synopsis: Accelerated Molecular Dynamics was used to simulate the recruitment of the glutamine substrate by γ-glutamyltransferase. A swarm of independent simulations allowed us to describe the enzyme-substrate recognition and binding process at the atomic level without any prior assumption concerning the association pathway. This approach can be successfully used to model the molecular recognition process in any protein-ligand system.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-124

Author: Aleksandr Prokopenko

Title: Computational investigation on photonics of boron and zinc dipyrromethene complexes

Synopsis: New dipyrromethenes are been synthesizing with increasing intensity but at the same time theoretical researches of their physical and chemical properties to develop optical devices is going essentially slower. Experimental investigation complemented with theoretical-computational studies accompaniment lead to deeper understanding of electronic structure, pathways of electronic transitions, and specific spectral-luminescence features to develop more efficient optical devices.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-125

Author: Nicholas Hill

Title: Internal Oriented Electric Fields as a Strategy for Selectively Modifying Photochemical Reactivity

Synopsis: Here, we present a proof-of-concept study into the feasibility of applying static electric fields as a way of tuning photochemical behavior, using charged functional groups (acid/base groups) as the means by which the electric field is applied. We demonstrate that, with acetophenone, the electric field effects are large, usable, and persistent in high-polarity solvents.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-126

Author: Jon Paul Janet

Title: Uncertainty estimation for exploring chemical space with neural networks

Synopsis: We introduce a new metric for model uncertainty for chemical discovery with neural networks based on distances in the model-induced latent space and show that this metric provides superior out-of-sample error control compared to an ensemble approach and Monte Carlo dropout on low-information inorganic and organic problems. This metric could be used to better understand the coverage of chemical space with existing datasets and to drive active learning.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-127

Author: Haizhu Yu

Title: Theoretical investigation in preparing water-soluble Au25-nMn (M = Au, Ag, Cu, Pd, Pt) Nanoclusters with atomic precision

Synopsis: The water-soluble metal nanoclusters have shown great potential in bio-imaging, diagnosis, and therapy for heavy ills (such as cancer, Parkinson’s disease etc.). However, their atomic structures have been rarely reported, especially with the single crystallization skills. In this study, the possibility and the inherent determinants for formation of atomically precise M25 nanoclusters (with cysteine ligands) were probed with density functional theory methods.

Room: Arbeidskontoret-1+2

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Poster: P1-128

Author: Hasup Lee

Title: Prediction for photophysical properties of thermally activated delayed fluorescent emitters and application to carbazole-oxadiazole derivatives

Synopsis: We developed methods to predict properties of TADF materials based on TD-DFT. We applied our methods to carbazole-oxadiazole derivatives, and TADF devices made from carbazole-oxadiazole-based materials were shown to high external quantum efficiency.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-129

Author: Nadtanet Nunthaboot

Title: Understanding of binding molecular mechanism of hemagglutinin H3N2 of influenza virus complexed with arbidol and derivatives: A molecular dynamics simulation perspective

Synopsis: This work investigates the binding molecular mechanism of hemagglutinin H3N2 of influenza virus complexed with arbidol and its derivatives by means of molecular dynamics simulation. The result showed that arbidol derivatives could form strong hydrogen bonds with surrounding amino acids such as THR59 (HA2), ASP90 (HA2), LYS307 (HA2), GLU103 (HA2), LYS58 (HA2) and ASN60 (HA2), while arbidol is not able to make this kind of interaction. Moreover, the binding free energy prediction is in agreement w

Room: Arbeidskontoret-1+2

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Poster: P1-130

Author: Heng-Kwong Tsao

Title: Hybrid membranes of lipids and diblock copolymers : from homogeneity, raft, to phase separation

Synopsis: In this work, we found that he transition from the mixing state (homogenous distribution) to demixing state (formation of bilayered lipid-rich domains) is always observed as the lipid concentration exceeds a critical value. Phase separation is driven by weak energy incompatibility between lipids and copolymers. Also, size mismatch between copolymers and lipids induces the formation of monolayer lipid rafts, and tends to retard the occurrence of the demixing state.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-131

Author: Thomas Schaupp

Title: A classical ride through a conical intersection

Synopsis: We regard the dynamics in a coupled electron-nuclear model system at a conical intersection (CI). The quantum and classical motion is compared. The trajectories, moving in the complete phase space, are able to track the quantum wave packet motion through the CI. This, however, is not the case for a circular motion around the location of the CI.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-132

Author: Jesus Pérez-Ríos

Title: Slowing and cooling of AlF molecules

Synopsis: Here, we present a joint theoretical-experimental study about slowing and trapping of AlF down to temperatures $\sim$100$\mu$K. In particular, the measured and available spectroscopy information for the X$^1\Sigma$, a$^3\Pi$ and A$^1\Pi$ electronic states is inverted to get the pertinent potentials, and realistic Franck-Condon factors. As a result, only a re-pump laser will be required for the cooling of AlF.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-133

Author: Justin Tze-Yang Ng

Title: In-silico Modeling of the HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) Alpha-1 Complex

Synopsis: HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) is a tumoricidal complex of partially unfolded Alpha-lactalbumin and Oleic Acid. No high resolution structural model detailing atomistic interactions is available. Hamiltonian Replica Exchange Molecular Dynamics simulations sampled the conformational landscape and modelled the interactions between the Alpha1 peptide derived from HAMLET, and oleic acid.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-134

Author: Jan Vícha

Title: Periodic Trends of Spin-Orbit Heavy Atom on the Light Atom Effect to NMR Chemical Shifts Rationalized

Synopsis: The electronic structure-related principles and mechanisms that dictate the size and sign of the spin-orbit Heavy-Atom on the Light Atom (SO-HALA) NMR chemical shifts in heavy-element complexes are explained from first principles on example of 6th period hydrides, generalized across the Periodic Table and correlated with spin-orbit induced depletion/concentration of electron density at the light atom nucleus. Potential applications of the SO-HALA NMR chemical shifts are discussed as well.

Room: Arbeidskontoret-1+2

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Poster: P1-135

Author: Sanchit Chhabra

Title: Ultracold Rotational Quenching of NCCN Collision with 3He and 4He

Synopsis: Rotational quenching cross sections and rate coefficients have been calculated in the ultracold region using the He–NCCN potential energy surface computed at the CCSD(T)/aug-cc-pVQZ level of theory.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-136

Author: Cristopher Camacho

Title: A GPU-accelerated implementation of DFTB+

Synopsis: A GPU-accelerated implementation of the software DFTB+ is presented. Several benchmark calculations are carried out to assess the speed-up of the code.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-137

Author: Jasmin Süß

Title: Mapping of exciton-exciton annihilation in a molecular dimer via fifth-order femtosecond two-dimensional spectroscopy

Synopsis: We present a theoretical study on exciton-exciton annihilation (EEA) in a molecular dimer. This process is monitored using a fifth-order coherent two-dimensional (2D) spectroscopy as was recently proposed by Dostál et. al. (Nat. Commun. 9 (2018), 2466). Using an electronic three-level system for each monomer, we analyze the different paths which contribute to the two-dimensional spectrum. It is shown that signals are obtained which exhibit fingerprints of the EEA process.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P1-138

Author: Robert Polly

Title: Incorporation of radionuclides in hydroxycarbonate and hydroxychloride green rust

Synopsis: Deep geological disposal is considered a prime solution for the safe management of high-level nuclear waste (HLW). Over extended period of time, ground water may reach the canisters which will corrode, resulting in the formation of secondary Fe phases. Typical corrosion products are mixed-valent Fe(II/III) minerals such as magnetite or green rust (GR). In this study we focus on the incorporation of radio nuclides in hydroxycarbonate and hydroxychloride GR.

Room: Arbeidskontoret-1+2

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Poster: P1-139

Author: Matej Veis

Title: Linear scaling reduction scheme based on pair-MP2 for periodic systems

Synopsis: A ring of hydrogen atoms is studied by MP2 in the reciprocal space. Restricting the second order contributions to doubly occupied (opposite) pairs works reasonably well, but is generally not size extensive. An effort has been put to find an approximate reduced MP2 scheme that is size extensive and scales favourably with the number of basis elements. Presented method is benchmarked against MP2 in both direct and reciprocal space, and yields good results for the thermodynamic limit.

Room: Arbeidskontoret-1+2

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Poster: P1-140

Author: Hirotoshi Mori

Title: Is it possible to predict excess properties of mixed solvents by ab initio molecular simulation?: Effective fragment potential version 2 – Molecular dynamics (EFP2-MD) Simulation study

Synopsis: Predicting excess properties of mixed solvents by EFP2-MD.

Room: Arbeidskontoret-1+2

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Speaker: Şule Atahan-Evrenk

Title: Prediction of Intramolecular Reorganization Energy Using Machine Learning

Synopsis: We investigated the possibility of the prediction of the intramolecular reorganization energy (RE) for p-type organic molecular semiconductors from molecular structure only and showed that the RE could be predicted with a 12 meV root mean squared and 6meV mean absolute error.

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Speaker: Berta Fernandez

Title: Pursuing accuracy in intermolecular potentials and spectra

Synopsis: We obtained a highly accurate ground-state intermolecular potential for the CO-N2 complex and computed the corresponding rovibrational energies. The agreement with respect to experiment is among the best reported in the literature. In the second part of the talk, I will show results on the reparametrization of semiempirical potentials to improve the description of non-covalent interactions within the MOPAC program and present results on vibrational circular dichroism spectra of phenylacetylenes.

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Speaker: Bjørn Olav Brandsdal

Title: Computation of enzyme cold adaptation

Synopsis: The speed of chemical reactions in water and in enzymes varies with temperature, depending on how the free energy of activation is partitioned into enthalpy and entropy. In enzymes, this partitioning is also optimized as a consequence of the organism's adaptation to the environment. We will show how the temperature dependence of chemical reaction rates can be obtained from brute force computer simulations. Such calculations shed new light on how protein structures have evolved in differently adapted species.

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Speaker: Thomas Heine

Title: Challenges for automated materials discovery

Synopsis: After a report on data-driven discovery of two-dimensional materials, we will present components of a machinery which we develp to tailor metal-organic frameworks for specific applications.

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Speaker: Patrick Norman

Title: VeloxChem: an efficient implementation of real and complex response functions at the level of Kohn–Sham density functional theory

Synopsis: With the ease of Python library modules, VeloxChem offers a front end to quantum chemical calculations on contemporary high-performance computing (HPC) systems and aims at harnessing the future compute power within the EuroHPC initiative.

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Speaker: Nathalie Reuter

Title: Interfacial choline-aromatic cation-pi interactions can contribute as much to peripheral protein affinity for membranes as aromatics inserted below the phosphates

Synopsis: Unlike transmembrane proteins, peripheral membrane proteins rely on membrane binding interfaces that are restricted to a small part of their exposed surface and the ability to engage in strong selective interactions with membrane lipids. Our computational investigations of cation−π interactions between the three aromatic amino acids and choline groups of membrane lipids quantifies the contribution of those cation-π interactions to peripheral protein affinity for membranes.

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Speaker: Alan Aspuru-Guzik

Title: The Materials for Tomorrow, Today.

Synopsis: In this talk, I argue that for materials discovery, one needs to go beyond simple computational screening approaches followed by traditional experimentation. I have been working on the design and implementation of what I call “materials acceleration platforms” (MAPs). MAPs are enabled by the confluence of three disparate fields, namely artificial intelligence (AI), high-throughput quantum chemistry (HTQC), and robotics. The integration of prediction, synthesis and characterization in an AI-drive

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Speaker: Sonia Coriani

Title: Molecular Properties and Interactions: A Wonderful Playground for a Theoretical Chemist

Synopsis: Molecular properties are fundamental quantities underlying the macroscopic behavior of matter and their determination constitutes one of the most fruitful areas of interplay between experiment and theory. Examples sampled from our recent and past efforts in this area will be presented.

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Speaker: Teresa Head-Gordon

Title: How to Make an Enzyme: Computational Optimization of Electric Fields for Better Catalysis Design

Synopsis: We consider natural and de novo enzyme design and factors such as active site energetics, entropy of individual residues, dynamical correlations of enzyme motions, and electric fields as a way to exploit the entire protein scaffold to improve upon the catalytic rate. Using these principles, we show how other biomimetic catalytic constructs can be formulated, illustrated by a supramolecular capsule gold catalyst for carbon-carbon reductive elimination.

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Speaker: Shaul Mukamel

Title: Ultrafast spectroscopy and imaging of molecules with classical, quantum, and noisy x-ray pulses

Synopsis: Short x-ray pulses provide novel ways for exploring electron and nuclear dynamics in molecules. Core excitations allow to probe excited molecules in the vicinity of selected atoms. Stimulated Raman and diffraction signals will be presented and applied to nonadiabatic dynamics at conical intersections. The extra information provided by quantum and stochastic pulses will be discussed.

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Speaker: Angelos Michaelides

Title: Towards an improved understanding of interfacial water

Synopsis: In this talk I will discuss some of our recent work on water and ice probed with electronic structure methods

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Speaker: Anna-Sophia Hehn

Title: Explicitly correlated wave function approaches based on the random phase approximation

Synopsis: We present explicitly correlated wave function approaches based on the random phase approximation, showing that basis-set convergence can be as much accelerated as for state-of-the-art explicitly correlated coupled cluster methods, enabling to reach the basis-set limit efficiently and thus fostering the method's applicability for small-gap systems and dispersion interactions.

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Speaker: Malgorzata Biczysko

Title: From spectroscopic signatures to 3-D structure of protein building blocks

Synopsis: We aim at integrating diverse experimental spectroscopic data recorded for protein building blocks through quantum chemical computations. Effective computation strategy is developed starting from highly accurate theoretical models and/or state-of-the art experimental data for isolated amino acids and small peptides, gradually moving towards larger and more complex molecular systems featuring dispersion interactions, hydrogen bonding, variable local stereochemistry-conformation, and chirality.

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Speaker: Mariana Rossi

Title: Anharmonic Nuclear Quantum Effects and their Interplay with the Electronic Structure of Weakly Bonded Systems

Synopsis: In organic weakly bonded systems, the quantum nature of the nuclei and anharmonic contributions to nuclear motion can be particularly pronounced. I will present techniques based on path integral methods that approximate nuclear quantum dynamics (vibrational signatures, reaction rates, etc.) of molecules, organic solids, and organic-inorganic interfaces including all these effects. I will also show how the coupling to nuclear fluctuations can change the electronic structure of interfaces.

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Speaker: Seiichiro L. Ten-no

Title: Explicitly correlated F12 theory on modern electronic structure calculations

Synopsis: The development of F12 theory is reviewed forcusing on the introduction of the rational generator and Slater-type correlation factor.

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Speaker: Jonathan Tennyson

Title: The ExoMol project: molecular line lists for the opacity of exoplanets and other hot atmospheres

Synopsis: The ExoMol project aims to provide comprehensive line lists for models of hot astronomical bodies which contain molecules. Spectroscopic line lists are computed using variational nuclear motion programs, ab initio dipole moment surface and potential energy surfaces which are obtained by tuning ab initio surfaces using experimental data. Calculated line lists for over 50 molecules are available as part of the ExoMol database (www.exomol.com)

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Speaker: Michele Ceriotti

Title: Efficient Modeling of Thermal and Quantum Fluctuations in Materials and Molecules

Synopsis: Simulations that treat fully ab initio the thermodynamics of molecules and condensed phases are becoming increasingly accessible thanks to a combination of enhanced statistical sampling and accurate potentials based on machine-learning. I will discuss some of the most recent algorithmic developments, and present a few example applications.

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Speaker: Jan M. L. Martin

Title: Do CCSD and Approximate CCSD-F12 Variants Converge to the Same Basis Set Limits? The Case of Atomization Energies

Synopsis: In principle CCSD and CCSD-F12 should of course converge to the same basis set limit. For practical basis sets and the approximate CCSD-F12b, etc. models, there is a gap that is roughly proportional to various gauges for nondynamical correlation. This gap is due to neglected higher-order coupling terms in F12b. The more elaborate CCSD(F12*) model includes them, and does not suffer from this problem.

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Speaker: Elke Fasshauer

Title: Time-Resolved Measurement of Interparticle Coulombic Decay Processes

Synopsis: We present the first time-resolved description of resonant Interparticle Coulombic Decay based on the emitted electron. We show, how the process can be measured, propose a new way to determine its lifetime and how to extract information about nuclear motion prior to the decay.

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Speaker: Francesco Paesani

Title: Nuclear Quantum Effects in Ion-Mediated Hydrogen-Bond Rearrangements

Synopsis: State-of-the-art quantum dynamics simulations demonstrate tunneling in hydrogen-bond rearrangements in halide-water complexes. A systematic analysis of the tunneling pathways provides fundamental insights into the competition between halide−water and water−water interactions. These results suggest that nontrivial many-body effects may also be at play in the hydration shells of halide ions in solution, especially in frustrated systems with dangling OH bonds.

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Speaker: Ludwik Adamowicz

Title: Quantum-mechanical non-Born-Oppenheimer calculations of small atoms and molecules.

Synopsis: In this presentation I will describe the work carried out in my group concerning the development of quantum-mechanical methods for calculating bound states of small atoms and molecules without assuming the Born-Oppenheimer approximation. In the non-BO approach all particles forming the system (nuclei and electrons) are treated on equal footing. The energies of the states, which in the case of atoms include electronic ground and excited states and in the case of molecules include a combination of

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Speaker: Thomas F. Miller

Title: Classical and Machine-Learning Methods for Quantum Simulation

Synopsis: The talk will focus on recent developments and applications of Feynman path integral methods for the description of chemical dynamics. Additionally, we will describe a machine-learning approach to predicting the electronic structure results on the basis of simple molecular orbitals properties, yielding striking accuracy and transferability across chemical systems at low computational cost.

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Speaker: Irene Burghardt

Title: High-Dimensional Quantum Dynamics of Functional Organic Polymer Materials: Coherence, Confinement, and Disorder

Synopsis: We report on high-dimensional quantum dynamical simulations that highlight the intricate interplay of electronic delocalization, coherent vibronic dynamics, trapping phenomena, and disorder effects in the elementary transfer events in functional organic polymer materials. To this end, advanced multiconfigurational methods of the MCTDH family are employed in conjunction with first-principles parametrized lattice Hamiltonians that accurately capture vibronic effects.

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Speaker: Volker Blum

Title: Accurate, Scalable All-Electron Theory Across the Periodic Table: Organics, Inorganics, Hybrids

Synopsis: This talk covers recent developments on accurate, scalable all-electron theory of materials and molecules using numeric atom-centered basis functions in the FHI-aims code. We review the open-source ELSI infrastructure for massively parallel (generalized) Kohn-Sham solutions; GPU developments; spin-orbit coupling and large-scale hybrid DFT; and computational predictions for new, crystalline, electronically tunable layered organic-inorganic hybrid semiconductors enabled by our developments.

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Speaker: Claudia Filippi

Title: The force awakens in quantum Monte Carlo

Synopsis: We exploit here our recently developed formalism to compute energy derivatives in quantum Monte Carlo (QMC) with the same numerical scaling as the energy alone. By fully optimizing wave function and structural parameters, we can explore the performance of the method and show that the use of compact determinant components obtained in a selected-configuration-interaction scheme leads to chemically accurate ground- and excited-state structures, and vertical and adiabatic excitation energies in QMC.

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Speaker: Stefan Grimme

Title: New Tight-Binding Quantum Chemistry Methods for the Exploration of Chemical Space

Synopsis: The GFN-xTB family of tight-binding methods is discussed which focus on the computation of geometries, vibrational frequencies, and non-covalent interactions. Recently, they have been extended by including multipole electrostatics leading to higher accuracy at lower empiricism. An even faster first-order form with classical electrostatics is briefly described. The methods are effectively used in the framework of meta-dynamics to globally explore compound, conformer, and reaction space.

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Speaker: Madhurima Jana

Title: Stability of Proteins in Solutions: A Microscopic Investigation on the Role of Surrounding Water/Cosolvent

Synopsis: The three dimensional folded native structure of proteins need to be preserved to conserve their biological activities and to avoid unwanted immunological reactions. Presence of additives in solution plays important role on such matter. In this presentation I shall discuss the concentration dependent effects of cosolvent on proteins and the underlying mechanism by which cosolvent destabilizes or preserves the protein's structure.

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Speaker: Christian Ochsenfeld

Title: Quantum-chemical methods for biochemical systems

Synopsis: Linear- and sublinear-scaling DFT, MP2, and RPA methods are presented that allow for unique insights into biochemical processes. Example applications include the nucleotide discrimination by RNA polymerase or DNA repair processes. Further insights into molecular transformations open up by a new approach for localizing free energy changes.

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Speaker: Brenda Rubenstein

Title: Ab Initio Finite Temperature Auxiliary Field Quantum Monte Carlo for Solids

Synopsis: In this work, we present an Auxiliary Field Quantum Monte Carlo method for studying the finite temperature electronic structure of any system that can described by an ab initio Hamiltonian. We demonstrate the accuracy of this approach for benchmark molecules and solids, and compare it to more popular mean field treatments of real materials. Our method serves as a new, robust tool for studying low, but finite temperature phase transitions.

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Speaker: Lyudmila Slipchenko

Title: Polarizable embedding for biological systems: Modeling photoactive proteins with the Effective Fragment Potential method

Synopsis: The effective fragment potential (EFP) is a polarizable model providing rigorous description of non-covalent interactions from first principles. We present an overview of recent developments of the EFP method and, on example of the Fenna-Matthews-Olson photosynthetic pigment-protein complex, demonstrate that polarizable embedding is essential for predictive modeling of electronic properties and spectroscopy of photobiological systems.

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Speaker: Michele Cascella

Title: Simulating Biological Systems Coupling Particles and Fields with Molecular Dynamics

Synopsis: The hybrid particle-field with molecular dynamics (hPF-MD) is a newly-established methodology based on density-functional potentials for the simulations of molecular systems capable of treating large-scale soft matter systems using relatively small high-performance architectures. I will present some of the newest developments in hPF-MD for biosystems, including the treatment of polyelectrolyte solutions, and the first hPF-MD model for peptides.

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Speaker: Joost VandeVondele

Title: Linear scaling DFT accelerated with GPUs and ML

Synopsis: Linear scaling DFT with CP2K has been available for a number of years, and is enabled by a sparse matrix library, DBCSR. This freely available and highly efficient, MPI parallel, thread and GPU-accelerated library employs machine learned GPU kernels to reach high performance. Using adaptive basis sets, inferred from available data, large scale DFT calculations at tight-binding cost have become possible.

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Speaker: Fabien Bruneval

Title: The linearized GW density matrix

Synopsis: Using the GW approximation to the self-energy, we have obtained a compact expression for the density matrix that we have named linearized GW density matrix. It allows one to obtain an improved density matrix (and density) directly from “one-shot” calculations. It yields excellent densities, Hartree, and exchange energies as compared to CCSD.

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Speaker: Attila Csaszar

Title: Quasistructural molecules

Synopsis: For quasistructural molecules the notion of a static equilibrium structure looses its strict meaning, rotations and vibrations become dominant, separation of the internal nuclear motions breaks down, classification of the rovibrational states requires the use of permutation-inversion symmetry and molecular-symmetry groups, and some of the rovibrational eigenenergies assigned to a vibrational parent state exhibit unconventional (in the most striking cases “negative”) rotational contributions.

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Speaker: Mikko Karttunen

Title: Computational modelling of cellulose and its modifications

Synopsis: I will discuss computational modeling of cellulose, the most common organic polymer on earth, and its use in applications such as wound dressing and artificial joints and bone.

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Speaker: Steven G. Louie

Title: Many-electron Correlations in Multi-particle Excitations and Nonlinear Optical Processes in Materials

Synopsis: Using an interacting Green’s function approach, we present the theory and applications of: 1) a new formalism and computational method for 3- and 4-particle correlated excitations in solids, with applications to trions and bi-excitons in reduced-dimensional materials; and 2) a time-dependent GW approach for time-dependent processes and nonlinear optics, which has led to our discovery of giant exciton effects in shift currents in two-dimensional semiconducting materials.

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Speaker: Katarzyna Pernal

Title: Dynamic Correlation for CASSCF Reference with Adiabatic Connection Approaches: Open Shell Systems and Dispersion Interaction

Synopsis: The adiabatic connection derived approach to dynamic correlation energy for CASSCF wavefunction is presented. Its extension to open-shell systems is introduced and good performance, comparing with perturbation methods, is illustrated for closed and open-shell molecules.

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Speaker: Tatiana Korona

Title: On the Applicability of Various Partitioning Schemes to Intermolecular Interactions

Synopsis: Various partitioning schemes, like F-SAPT, QTAIM, IQA, SMF, were critically evaluated to test their usefulness to describe intermolecular interactions and to reveal the relative importance of the interactions between pairs of functional groups.

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Speaker: Monika Fuxreiter

Title: Conformational heterogeneity in enzymatic catalysis and evolution

Synopsis: We explored the link between conformational plasticity and evolvability of designed enzymes via multiscale simulations. Optimisation of reorganization energy was the major driving force in evolving KE07 and HG3.17 Kemp eliminases. Conformational heterogeneity persisted during both trajectories and catalytic rates were robust to significant changes in the ensemble. This promoted specialization, suggesting a role of conformational heterogeneity in shaping the functional repertoire of enzymes.

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Speaker: Satoshi Maeda

Title: Systematic Generation and Analysis of Reaction Path Networks by the Artificial Force Induced Reaction Method

Synopsis: To systematically generate and analyze reaction path networks, we have developed the artificial force induced reaction method and the rate constant matrix contraction method, respectively. By combining these methods, an approach which identifies the product, all byproducts, their generation ratios, as well as their generation mechanisms starting from a set of reactants and catalysts has been established. In my talk, these methods and some application examples are presented.

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Speaker: Fernando Martin

Title: Attosecond pump-probe spectroscopy of molecular electron dynamics

Synopsis: The results of attosecond pump-probe theoretical simulations in which several molecules are ionized with a single attosecond pulse (or a train of attosecond pulses) and are subsequently probed by one or several infrared or xuv few-cycle pulses will be presented. Electron dynamics in the photo-excited molecule or remaining molecular ion is revealed by varying the pump-probe delay with attosecond time resolution.

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Speaker: Guido Pupillo

Title: Cavity-induced collective dissipation for cold chemistry

Synopsis: In this talk we discuss the opportunity to combine cavity quantum electrodynamics and cold chemistry, by proposing to utilize an optical cavity to form ground-state molecules from ultracold atoms. We show theoretically that collective effects in the dissipative dynamics can provide a robust alternative to current techniques, such as photoassociation or STIRAP-based techniques. We conclude with a perspective of possible applications of cavity-QED in cold chemistry and materials science.

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Speaker: Natalie Fey

Title: CatLab – Putting calculation before experiment in organometallic catalysis

Synopsis: Computational studies of homogeneous catalysis play an important role in furthering our understanding of catalytic cycles and can guide the discovery and evaluation of new catalysts. An iterative process of mechanistic study, data analysis, prediction and experimentation can accommodate complicated mechanistic manifolds and lead to useful predictions for the discovery and design of suitable catalysts and I will discuss some recent examples of work in our group.

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Speaker: Eberhard Gross

Title: Potential energy surfaces and Berry phases from the exact factorization: A rigorous approach to non-adiabatic dynamics

Synopsis: Based on the exact factorization of the full electron-nuclear wave function, we propose a novel mixed-quantum-classical approach to non-adiabatic dynamics whose unique feature is that the trajectories are coupled. Without recourse to Tully surface hopping and without any added decoherence corrections, the new algorithm provides a very accurate (much improved over surface hopping) description of decoherence. This is demonstrated for the photo-induced ring opening of oxirane.

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Speaker: Olivier Dulieu

Title: Ultracold doubly-polar molecules: on the way to create them via a Laser-Assisted Self-Induced Feshbach Resonance

Synopsis: We propose a new type of Feshbach resonance: the Light-Assisted Self-Induced Feshbach Resonance (LASIFR), where the closed and open coupled channels are both associated with the electronic ground state of a heteronuclear diatomic molecule. A sub-THz photon couples the pair of ultracold atoms, occupying for instance the lowest motional state of an optical lattice, site, to a bound rovibrational state close to the dissociation limit. We exemplify this proposal with the case of RbSr.

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Speaker: Markus Reiher

Title: Quantum Chemical Exploration of Catalytic Reaction Networks

Synopsis: This talk will discuss a massively automated reaction-network exploration algorithm based on first-principles heuristics and equipped with seamless uncertainty quantification up to the level of kinetic modelling.

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Speaker: Nina Rohringer

Title: Stimulated X-Ray Emission Spectroscopy for Chemical Analysis

Synopsis: XFELs deliver fs X-ray pulses at unprecedented intensities and open avenues for studying x-ray nonlinear processes. An intriguing perspective is the application of coherent attosecond nonlinear pump-probe techniques to study charge and energy transport in chemical reactions. Stimulated X-ray emission and X-ray scattering are the fundamental building blocks of these nonlinear spectroscopic techniques. Here we present results on amplified spontaneous K-α spectroscopy of Mn compounds in solution.

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Speaker: Robert Moszynski

Title: New physics with ultracold strontium molecules

Synopsis: During the last decade ab initio methods of quantum chemistry have been applied with success to interpret precision experiments on two-body processes in the ultracold regime. I will present recent examples of successful applications of the ab initio methods to describe two-body processes in atomic optical lattices leading to the formation of unusual chemical bonds, observations of exotic optical transitions, or photodissociation processes with full quantum state control.

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Speaker: Heather J. Kulik

Title: Transition metal catalyst discovery with high-throughput screening and machine learning

Synopsis: High-throughput and machine learning tools for discovery of selective and active open shell transition metal catalysts.

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Speaker: Boutheina Kerkeni

Title: Understanding H2 Formation on hydroxylated nanopyroxene clusters: Ab initio Study of the Reaction Energetics and Kinetics

Synopsis: It has been shown that the formation of the H2 molecule almost certainly occurs on dust grains of the ISM. Silicate dust constitutes one of the primary solid components of the Universe and are thought to be essential enablers for complex chemistry in a number of astronomical environments. Hydroxylated silicate nanoclusters are likely to be persistent in diffuse clouds. Reaction mechanisms for H2 formation on such grains were investigated using DFT calculations and semiclassical reaction kinetics.

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Speaker: Svetlana Kotochigova

Title: Nonadiabatic Transitions via Conical Intersections in Ultracold Chemical Reactions

Synopsis: It is now possible to investigate chemical reactions of small molecules at temperatures well below 1 mK, where quantum effects and threshold phenomena begin to dominate collisions. Here, we focuse on ultracold heteronuclear polar molecules that collide with atoms and form intermediate complexes with conical intersections (CIs), crossing lines between two or more potential surfaces.

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Speaker: Julien Bloino

Title: A Virtual Spectrometer to Predict and Interpret Vibrational Spectra

Synopsis: We present an integrated platform to predict and interpret spectra covering infrared to ultraviolet energy ranges. While describing some features of the tool, we explore recent achievements in the simulation of vibrational spectra for medium-to-large molecules beyond the harmonic approximation. Increase in system size poses challenges in terms of computational cost and reliability, which will also be addressed here.

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Speaker: Steven R. White

Title: Multisliced Gausslet Bases for Electronic Structure

Synopsis: Gausslets are a new type of basis set, based on wavelet technology, which allow strictly diagonal two electron Hamiltonians. Gausslets are smooth, highly local, orthogonal, and integrate like delta functions, giving them the diagonal property. In our multisliced gausslet formulation, they also have variable resolution, and can be combined with ordinary Gaussian bases. Here we given an overview of this technology, with applications to hydrogen chains using DMRG.

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Speaker: Barak Hirshberg

Title: Path Integral Molecular Dynamics for Bosons

Synopsis: We present a method for performing path integral molecular dynamics simulations of Bosons. The main challenge is enumerating all permutations of identical particles, feasible only for very small systems. We show that the forces and potential energy can be evaluated recursively, avoiding explicit enumeration of permutations, and resulting in an algorithm that scales cubically with system size. The method is applied to trapped Bosons, which are at the heart of emerging qunatum technologies.

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Speaker: Tucker Carrington

Title: Collocation methods for computing vibrational spectra

Synopsis: By using collocation, a Multi-Configuration Time-Dependent Hartree approach, hierarchical basis functions, that span the same space as the single particle basis, and a Smolyak grid, we have developed an approach that makes it possible to use MCTDH with a general potential and prune both the basis and the grid.

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Speaker: Garnet Chan

Title: Progress in quantum embedding in the condensed phase

Synopsis: I will discuss recent progress in quantum embedding approaches based on density matrix embedding and dynamical mean-field theory in ab initio descriptions of condensed phase systems.

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Speaker: Seogjoo Jang

Title: Quantum Fokker-Planck equation with positive definiteness condition via path integral influence functional formalism

Synopsis: Quantum Fokker-Planck equation (QFPE) offers a well-defined way to extend classical Brownian motion for quantum regime, but microscopic derivation of a satisfactory form of QFPE remains challenging. Best known form of QFPE is the one derived by Caldeira and Leggett (CL), which lacks positivity. This talk presents a generalization of CL-QFPE accounting for non-equilibrium effects and well-defined positivity condition.

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Speaker: Ad van der Avoird

Title: Spectra of O2 induced by collisions with N2 and O2

Synopsis: We computed O2-O2 and O2-N2 collision-induced spectra by ab initio electronic structure calculations of the relevant ground and electronic excited state interaction potentials and the transition dipole moment functions, followed by diabatization and quantum mechanical scattering calculations. We determined the underlying absorption mechanisms, which produce different spectral line shapes. Our results will be applied in calibrating satellite spectrometers used for remote sensing of the atmosphere

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Speaker: Philippe Corboz

Title: Simulation of strongly correlated systems with 2D tensor networks

Synopsis: In this talk I report on recent progress in simulating 2D strongly correlated systems with infinite projected-entangled pair states (iPEPS) - a 2D tensor network ansatz for 2D ground states in the thermodynamic limit. Simulation results for an extended 2D Hubbard model show that the ground state is a period-4 stripe, in agreement with experiments on the cuprates. I will highlight other recent directions, including the study of 2D quantum critical phenomena and systems at finite temperature.

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Speaker: Pierre-Nicholas Roy

Title: Quantum dynamics of confined molecules

Synopsis: We present methods for the study of the quantum dynamics of confined molecules. Many-body assembles are considered and connection to relevant experiments will be mode.

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Speaker: Fabien Gatti

Title: The polyspherical approach: recent applications to spectroscopy

Synopsis: The polyspherical coordinates allow one to describe motions of large amplitude in flexible and systematic ways. We will present applications to penta-atomic systems and to the Eigen cation in full dimensionality (33D).

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Speaker: Örs Legeza

Title: Attosecond electron dynamics via tensor network state methods in strongly correlated molecular systems

Synopsis: Quantum many-body systems out of equilibrium pose some of the most intriguing questions in physics and chemistry. We present a novel scheme and show that if the manifold containing both tensor network states and fermionic mode transformations is chosen, significantly longer times can be achieved. Recent developments on the externally corrected coupled cluster density matrix renormalization group method, fermionic orbital optimization, and time-dependent variational principle will be discussed.

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Speaker: Gregory A. Voth

Title: Coarse-graining of Feynman Path Integrals in Statistical Mechanics

Synopsis: The imaginary time Feynman path integral formalism for quantum statistical mechanics provides a way of understanding the nuclear quantum effects in complex condensed matter systems. Several numerical path integral based methods such as path integral molecular dynamics (PIMD), path integral Monte Carlo (PIMC), centroid molecular dynamics (CMD), and ring polymer molecular dynamics (RPMD) have been developed based on the quantum-classical isomorphism in which a completely classical “ring polymer” c

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Poster: P2-1

Author: Christophe Vaillant

Title: Quantum and Semiclassical Instanton Theories for Chemical Reaction Rates

Synopsis: We examine the links between two popular methods for calculation reaction rates, namely the quantum instanton and the semiclassical instanton. The quantum instanton is known to break down when the reaction barriers are highly asymmetric, whereas the semiclassical instanton remains accurate below the cross-over temperature. We identify the paths that contribute to the breakdown of the quantum instanton, and show that neglecting these paths recovers the accuracy of the semiclassical instanton.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-2

Author: Dongwook Kim

Title: Structure-property relationship of thermally activated delayed fluorescence (TADF) materials: Carbazole based organic emitters

Synopsis: Excited state natures of organic emitters are calculated and analyzed via quantitative assessment of charge transfer and local excitation characters and excitation energy decomposition. In addition, the effect of quasi-degeneracy of the excited states in particular on intersystem crossing rate of such molecules are discussed. A design rule for efficient thermally activated delayed fluorescence (TADF) emitters is proposed.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-3

Author: Emmanuel E. Moutoussamy

Title: Revisiting the role of electrostatic interactions in the membrane binding of peripheral proteins

Synopsis: The most widespread model of membrane binding described a mechanism where unspecific electrostatics is predominant. However, we have identified several enzymes that present a low electrostatic binding free energy for membrane models. We mapped the binding site of one of these enzymes, the phospholipase-D, using molecular dynamic simulations. We observed multiple cation-π interactions between aromatic residues and lipid heads. These interactions are essential for the binding.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-4

Author: Tobias Schäfer

Title: Low-complexity MP2 for solids

Synopsis: Standard approach in quantum chemistry to evaluate energy of matter: Hartree-Fock + MP2. However, for extended systems, this is rather costly. Conventional MP2 implementations scale with O(N^5). Here we present new and low complexity implementations that have a lower scaling and a very high parallelization efficiency.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-5

Author: Murilo Hoias Teixeira

Title: Calculation of redox potentials for iron-sulfur proteins

Synopsis: Metalloproteins are key components to energy transduction in several biochemical pathways through redox reactions. Here, we investigate isolated models of iron-sulfur cofactors and a simple protein, rubredoxin, to identify the main physical contributions to the calculation of redox potentials employing QM/MM hybrid methods. QM/MM region size, finite model effects, level of quantum-mechanical treatment, explicit hydration of cofactors and configurational sampling were evaluated.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-6

Author: Mats Simmermacher

Title: Electronic Coherence in Ultrafast X-Ray Scattering by Molecules

Synopsis: New X-Ray Free-Electron Laser facilities may permit the detection of a novel component in ultrafast non-resonant x-ray scattering by molecules. This component, termed “coherent mixed”, is caused by an intramolecular interference of scattering amplitudes of at least two coherently populated electronic states in a molecular wave packet. We show the first two-dimensional patterns of coherent mixed scattering and demonstrate that they provide a direct probe of the degree of electronic coherence.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-7

Author: Pradipta Samanta

Title: Study of photo-ionization processes using Full Configuration Interaction Quantum Monte Carlo

Synopsis: In this work we present a stochastic way of solving time-dependent Schrödinger equation in order to study photo-ionization processes of atoms.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-8

Author: Miquel Pons Viver

Title: Spin Projection made easy

Synopsis: We propose a new method for obtaining the operator matrix elements over spin projected wavefunctions, in which the spin symmetry of a broken symmetry Unrestricted Hartree-Fock determinant is recovered by the Löwdin formula. Compared to the naive expansion into Slater determinants, the new method enables the evaluation at a polynomial cost instead of the combinatorial one with the number of electrons.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-9

Author: Sarah Karbalaei Khani

Title: Systematic Evaluation of Reaction Field Schemes for Coupling COSMO Polarizable Continuum Model and Second-order Wavefunction Methods for Computing Solvatochromic Shift

Synopsis: In order to combine polarizable continuum models with a quantum mechanical description of the solute, various reaction field schemes have been introduced. We have systematically evaluated and compared three reaction field schemes including PTE, PTED and post-SCF for the calculation of solvatochromic shifts.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-10

Author: Małgorzata Olejniczak

Title: Topological Data Analysis in quantum chemistry - the electron density of Au complexes case study

Synopsis: We demonstrate the use of the Topological Data Analysis (TDA) for the electron density (ED) of Au complexes evaluated at different levels of accuracy. TDA tracks the evolution of critical points of data, hence if applied to ED, it has a direct connection to the Quantum Theory of Atoms in Molecules (QTAIM). Our study contributes to the discussion of the use of QTAIM for the non-covalent interactions, especially in relativistic regime, and proposes to consider TDA as a modern complement to QTAIM.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-11

Author: Julia Westermayr

Title: Excited-state machine learning molecular dynamics simulations on nanosecond time scales

Synopsis: Excited-state ab-initio molecular dynamics simulations are seriously limited by the underlying on-the-fly quantum chemical calculations, hampering their application for long time scales. With our newly developed machine learning approach, that learns the potential energy surfaces as well as corresponding forces and couplings between different electronic states of a molecule, we are able to carry out nonadiabatic dynamics simulations on a nanosecond time scale.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-12

Author: Antonio Prlj

Title: A Semiclassical Glimpse into the Azulene Photophysics and Spectroscopy

Synopsis: We employ the semiclassical multiple surface dephasing representation (MSDR) method to explain the unusual fluorescence properties of azulene molecule. To describe the important Herzberg-Teller and anharmonicity effects in absorption and emission vibronic spectra of azulene, semiclassical thawed Gaussian approximation (TGA) was employed.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-13

Author: Anthony Ferté

Title: Theoretical approach for simulating single photon double core ionization of small molecules

Synopsis: We present a theoretical approach for simulating single photon double core ionization of small molecules in the dipolar approximation. Our method couple a selected CI computation of wave functions to reduce the number of slater determinants needed to converge the peak relative energies and the use of non-orthogonal molecular orbital basis set for the neutral and the ionised system in order to speed up the convergence of the peak intensities.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-14

Author: Rafał Podeszwa

Title: Two- and three-body energies from the DLPNO-CCSD(T) method

Synopsis: Domain-based local pair natural orbital coupled cluster theory with single, double, and perturbative triple excitations [DLPNO-CCSD(T)] method was applied to calculations of two- and three-body intermolecular interactions energies of several van der Waals complexes. The large computational speed-up of the DLPNO-CCSD(T) method compared to the canonical CCSD(T) method is followed by decrease of the accuracy that is moderate for the two-body and fairly significant for the three-body energies.

Room: Margarinfabrikken-1+2+3

Abstract: download

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Poster: P2-15

Author: Yongbin Kim

Title: The effective modeling of photobiology with the Effective Fragment Potential method

Synopsis: The Effective Fragment Potential (EFP) is a quantum mechanical-based model for describing non-covalent interactions. EFP can be coupled with quantum mechanical methods in polarizable embedding QM/EFP schemes. We employed QM/EFP for investigating Fenna-Matthews-Olson (FMO) photosynthetic complex and showed that accurate structures of pigments and polarizable description of the protein are essential for predicting absorption and circular dichroism spectra in agreement with experimental findings.

Room: Skarven

Abstract: download

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Poster: P2-16

Author: Mira Diekmann

Title: Classification of Rotational Energy Levels within the Complete Nuclear Permutation Inversion Group

Synopsis: We use a system of 4 atoms as a minimal example for symmetry classification of rotational energy levels of a chiral system within the CNPI group. Within this group restrictions due to nuclear spin can be included as well as splitting of energy levels due to tunneling between enantiomers or between different versions of the enantiomer.

Room: Skarven

Abstract: download

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Poster: P2-17

Author: Anders Brakestad

Title: Static polarizabilities at the basis set limit: A benchmark of 128 species

Synopsis: In this work we quantify the basis set errors present in static polarizability calculations using large GTO basis sets. This is made possible due to the quasi-exact results that can be obtained by using multiwavelet basis functions. With a set of 128 small molecular and atomic species, we find that mostly GTOs perform very well, but some challenging cases are revealed among the open-shell species.

Room: Skarven

Abstract: download

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Poster: P2-18

Author: Erik Pillon

Title: Periodic orbits localization through energy frequency analysis in bound systems

Synopsis: In our work we have developed a molecular dynamics based approach where the kinetic energy spectrum is used to localize the periodic orbits. An extended normal mode like ansatz is introduced to decompose the phase space into harmonic periodic orbits. The kinetic energy spectrum is fitted by this ansatz to extract the fundamental frequencies of the system. Such kind of representation of the dynamics allows to pre- serve the simple normal mode like picture by renormalizing the harmonic frequencies

Room: Skarven

Abstract: download

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Poster: P2-19

Author: Anael Ben-Asher

Title: The effect of molecular geometry on He*-H2 autoionization reaction

Synopsis: Recently, a Penning ionization reaction was observed in the low temperature collision of an excited helium atom (3P,1s2p) and a hydrogen molecule. In our research, using ab-initio complex potential energy surfaces (CPESs), we study the effect of the molecular geometry on the reaction. Our results suggest that due to the large anisotropy of the CPESs, the collision reaction occurs mostly in a certain geometry (the B1 symmetry of the T-shape geometry).

Room: Skarven

Abstract: download

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Poster: P2-20

Author: Aleksandra Leszczyk

Title: Frozen-pair Coupled Cluster methods for strong and weak correlation

Synopsis: The major part of the strong correlation can be provided by the pair Coupled Cluster Doubles (pCCD) model combined with a (variational) orbital optimization protocol. The method is size-consistent and computationally inexpensive in comparison to other multi-reference approaches. One way to include the missing (dynamic) electron correlation effects is to use a frozen-pair (linearized) Coupled Cluster correction on top of the pCCD wave function.

Room: Skarven

Abstract: download

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Poster: P2-21

Author: Seungsoo Nam

Title: Separation of Density-Driven and Functional Error of Density Functional Calculations via Kohn-Sham Inversion

Synopsis: To understand the source of the error in DFT calculations, we separated total error of DFT into density-driven and functional errors via Kohn-Sham inversion technique. Density-driven error and functional error from semilocal functionals were in the same direction, while their sign depends on the exact-exchange portion in hybrid functionals, sometimes resulting cancellation of density-driven error and functional error.

Room: Skarven

Abstract: download

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Poster: P2-22

Author: Christian Mück-Lichtenfeld

Title: DFT Studies on Mechanism and Reactivity of Radicals generated from Boronic Esters

Synopsis: We have conducted DFT studies on the mechanism of radical reactions involving substituted boronic esters. New pathways to regioselectively add alkyl and aryl radicals to C-C double bonds have been developed. We discuss the reactivity and characteristic properties of radical intermediates including carbon centered radicals of borates and the radical adduct of bis(catecholato)borane containing a boron-boron one-electron σ bond.

Room: Skarven

Abstract: download

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Poster: P2-23

Author: Glib Baryshnikov

Title: Tetraoxa[8]circulene-Based Nanosheets as a New Family of Two-Dimensional Covalent Metal-Free Organic Frameworks

Synopsis: Hypothetically, some hetero[8]circulenes could be polymerized into zero-dimensional (0D) nanoclusters, one-dimensional (1D) nanoribbons, and two-dimensional (2D) nanosheets. Such reactions have been proven to be thermodynamically allowed through intermolecular dehydrohalogenation or Ullman polymerization. Here we report structural and electronic properties of a new family of two-dimensional covalent metal-free organic frameworks based on tetraoxa[8]circulene with different types of fusing.

Room: Skarven

Abstract: download

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Poster: P2-24

Author: David Wilson

Title: Theoretical Insights to Coordination Chemistry of Carbon: Novel Bonding and New Organic Chemistry

Synopsis: Coordination chemistry of carbon is an emerging field of organic chemistry. Outcomes from theoretical and experimental studies, employing donor ligands to stabilize various C2 containing fragments are presented with detailed theoretical analysis of bonding and electronic structure, including ligand stabilized acetylene and a cis-stabilized alkene. MO, NBO, QTAIM, I-SAPT, and EDA analyses provide an understanding of electronic structure, bonding, and non-covalent interactions.

Room: Skarven

Abstract: download

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Poster: P2-25

Author: James Gayvert

Title: Advancing CAP-EOM-CCSD scheme for electronic resonances: projected CAP scheme and Voronoi absorbing potential.

Synopsis: We present recent developments in the CAP-EOM-CCSD scheme for calculating positions and widths of electronic resonances. Specifically, we discuss the projected CAP-EOM scheme and the Voronoi absorbing potential applied to three types of systems: diatomic molecules, a localized resonance in a cluster, and a delocalized resonance.

Room: Prostneset

Abstract: download

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Poster: P2-26

Author: Nikolay Golubev

Title: On-the-fly ab initio semiclassical evaluation of electronic coherences in polyatomic molecules

Synopsis: Recent experiments measuring pure electronic dynamics in molecules demonstrated a strong influence of the slow nuclear motion on the ultrafast electronic one. In order to support these groundbreaking observations theoretically, a concerted treatment of the correlated electronic and nuclear motion is required. Here we present a semiclassical approach which combines efficient single trajectory description of the nuclear motion with advanced on-the-fly evaluation of the electronic structure.

Room: Prostneset

Abstract: download

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Poster: P2-27

Author: Sebastian Thallmair

Title: Optical signals of photosynthetic antenna complexes modulated by microsecond protein dynamics

Synopsis: We combine coarse-grained molecular dynamics with tools from machine learning, the excitonic Hamiltonian model, and quantum mechanical simulations to unravel the impact of microsecond protein dynamics on the spectroscopic properties of plant light-harvesting complex II. The obtained individual chromophore arrangements lead to significant fluctuations of the spectra.

Room: Prostneset

Abstract: download

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Poster: P2-28

Author: Ruslan Tazhigulov

Title: Decrypting Photoinduced Electron Transfer in Cryptochromes: First-Principles Study

Synopsis: We present the results of multi-level computational study of photoinduced electron transfer (PET) in cryptochromes by exploiting multiple computational chemistry methods from empirical coarse-grained description to atomistic QM/MM simulations. The computed from the first-principles parameters are utilized for evaluating efficiency of the first ultrafast step of competing conventional and alternative ET pathways by calculating the time scales and quantum yield from the population dynamics.

Room: Prostneset

Abstract: download

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Poster: P2-29

Author: Anna-Katharina Hansmann

Title: Acenes and their fluorinated derivatives as model systems for singlet heterofission

Synopsis: To overcome the Shockley-Queisser limit in photo voltaic cells, the process of singlet fission is of high interest in experimental and theoretical studies. By this process of bi-exciton formation, one can achieve better conversion efficiencies. Rather than singlet homofission, which takes place in the bulk of molecular crystals like pentacene, this study focuses on singlet heterofission. We discuss energy level matching and the aspect of coupling matrix elements for singlet heterofission.

Room: Prostneset

Abstract: download

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Poster: P2-30

Author: Maren Podewitz

Title: Quantum Chemical Microsolvation by Automated Solvent Placement

Synopsis: We developed a physics based approach to microsolvation, where we deduced the number and location of solvent molecules in an automated way based on the free energy solvation thermodynamics derived from Molecular Dynamics Simulations and Grid Inhomogeneous Solvation Theory. This allows to precisely define the number and positions of individual solvent molecules for subsequent quantum chemical studies. We showcased the applicability of this methodology for several biologically relevant molecules.

Room: Prostneset

Abstract: download

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Poster: P2-31

Author: Susi Lehtola

Title: Fully numerical calculations on atoms and diatomic molecules

Synopsis: I present recent progress on fully numerical calculations on atoms and diatomic molecules with the HelFEM program. HelFEM is open source, yields fully variational energies, affords stable and fast SCF convergence, and supports hundreds of density functionals via an interface to the libxc library.

Room: Prostneset

Abstract: download

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Poster: P2-32

Author: Marta Chołuj

Title: The molecular electric properties under the influence of spherical harmonic potential

Synopsis: Among many potentials that can be used to model the effect of spatial confinement the harmonic oscillator potential is one of the most widely applied. In this project, we studied the molecular electric properties in the presence of spherical harmonic potential and characterized the impact of the relative position of the considered molecules and spherical confinement on these properties. We also analyzed how the topology of confining environment affects dipole moment and (hyper)polarizability.

Room: Prostneset

Abstract: download

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Poster: P2-33

Author: Ádám Madarász

Title: Nuclear Quantum Effects from the Analysis of Filtered Trajectories

Synopsis: We report on significant improvements in theoretical calculation of nuclear quantum effects. Our method, Generalized Smoothed Trajectory Analysis can be readily applied to ab initio calculations as well as classical simulations of biomolecules. The concept is demonstrated on well-known physical properties such as zero-point energy, heat capacity, internal energy and radial distribution functions. We chose harmonic oscillator as the simplest test and liquid water as an extremely challenging case.

Room: Prostneset

Abstract: download

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Poster: P2-34

Author: Alice Cuzzocrea

Title: Excited states in QMC: Which wave function? Which variational principle?

Synopsis: We investigate the key ingredients needed to efficiently achieve reliable excitation energies in quantum Monte Carlo. In particular, we show that the use of selected configuration-interaction expansions leads to compact Jastrow-Slater wave functions and to a balanced description of the states. Furthermore, we analyze the use of different variational principles in quantum Monte Carlo comparing the results of state-specific variance minimization and state-average energy minimization.

Room: Prostneset

Abstract: download

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Poster: P2-35

Author: Shuo Li

Title: Vanadium Tetrasulfide Nanowires: Half-metal Antiferromagnetic Semiconductor with Carrier Doping towards Antiferromagnetic Spintronics

Synopsis: Antiferromagnetic (AFM) spin devices could be one of the representative components for spintronic applications. However, detecting and manipulating the spin in AFM materials is still a challenge because of the absence of a net magnetic moment and spin degeneracy in the band structure. The gate voltage can manipulate the spin orientation of low dimensional materials leading to a transition from AFM to half-metal antiferromagnets.

Room: Prostneset

Abstract: download

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Poster: P2-36

Author: Derk P. Kooi

Title: A Variational Approach to London Dispersion Interactions Without Density Distortion

Synopsis: London dispersion interactions are one of the main challenges for Density Functional Theory (DFT) today. In our work we have introduced a class of variational wavefunctions that capture the long-range interaction between systems (atoms and molecules) without changing the diagonal of the density matrix of each monomer. We obtain virtually exact results for the interaction between two hydrogen atoms and very accurate results for small systems.

Room: Prostneset

Abstract: download

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Poster: P2-37

Author: Abril C. Castro

Title: Relativistic and Dynamic effects in Computational 1H-NMR Spectroscopy of Iridium Polyhydride complexes

Synopsis: We have established a computational protocol for the accurate calculation of 1H-NMR chemical shifts of iridium polyhydride complexes by accurately taking into consideration relativistic effects and conformational dynamics.

Room: Prostneset

Abstract: download

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Poster: P2-38

Author: Ágnes Szabados

Title: Ring Coupled Cluster Doubles at the Multireference Level

Synopsis: Ring approximation within the internally contracted MRCC framework of Mukherjee et al. is worked out and tested for torsional potentials and covalent bond breaking. Original version of the theory is amended with treatment of redundancy among double excitations. In addition terms of the equations are expanded to involve cumulants up to rank four. Reason for the latter step is that truncation at cumulant rank two results in inaccurate energy values with significant MR character of the reference.

Room: Prostneset

Abstract: download

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Poster: P2-39

Author: Nanna H. List

Title: Probing Ultrafast Photodynamics in Malonaldehyde with Transient X-ray Absorption

Synopsis: Excited-state hydrogen transfer (ESHT) is a fundamental chemical reaction of relevance throughout chemistry and biology. While malonaldehyde (MA) is a prototypical ESHT example, relatively little is known experimentally about its excited-state dynamics. Here we perform an in silico transient X-ray absorption spectroscopy experiment at complementary C and O K-edges and demonstrate its potential to disentangle the ultrafast relaxation in MA following excitation to S2.

Room: Prostneset

Abstract: download

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Poster: P2-40

Author: Erik Kjellgren

Title: MC-srDFT triplet response

Synopsis: Combing CASSCF and DFT in the framework of srDFT gives rise to a model that is able to describe static correlation (long-range) and dynamic correlation (short-range). Recently this model has been extended to triplet linear response for a singlet reference wave function, unlocking properties like triplet excitations and spin-spin coupling constants. Furthermore, to improve the accuracy of the MC-srDFT model our implementation has also been extended to work with meta-GGAs using srTPSS.

Room: Prostneset

Abstract: download

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Poster: P2-41

Author: James Cheeseman

Title: Theoretical Prediction of Resonance Raman and Resonance Raman Optical Activity Spectra

Synopsis: We present a fully analytic derivative extension of the damped linear response method to compute the resonance vibrational Raman and Raman optical activity of molecules using density functional theory. This approach also allows the Raman/ROA tensors and force field to be computed separately and at different levels of theory.

Room: Prostneset

Abstract: download

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Poster: P2-42

Author: Steffen M. Giesen

Title: Modeling Localised Excitations and Electron Transfer with a Non-orthogonal Product Wave Function Approach

Synopsis: A non-orthogonal product wave function approach is employed for the description of intermolecular transfer of electrons and electronic excitations. The building blocks for the multi-state approach are spin-adapted single determinants of the building blocks of an extended system.

Room: Prostneset

Abstract: download

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Poster: P2-43

Author: Peter Nagy

Title: Approaching CCSD(T)/CBS energies for molecules of up to 1000 atoms: method development and benchmark applications

Synopsis: The LNO-CCSD(T) method, utilizing systematically improvable local approximations, can reliably recover exact CCSD(T) energies within a third of a kcal/mol for systems of 30-63 atoms, and can match accurate CCSD(T)/CBS estimates up to 100 atoms within half kcal/mol. Even with QZ basis sets the new code requires a few 10 GBs of memory and disk space, and runs about 5-10x longer than efficient DF-HF. Large-scale LNO-CCSD(T)/QZ calculations are presented for protein-ligand binding up to 1000 atoms.

Room: Importkompaniet

Abstract: download

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Poster: P2-44

Author: Jan Paul Menzel

Title: Photoinduced Electron Injection and Charge Separation in a Dye-sensitized Photoanode: A Quantum-classical Semiempirical description

Synopsis: We explore the photoinduced electron injection and charge separation in a dye-sensitized photoanode via a combination of Density Functional based Tight Binding (DFTB) and quantum dynamics based on an extended Hückel Hamiltonian. This method seems to be a good compromise between accuracy and computational cost given the complexity of the system. Special focus is laid on the effect of nuclear motion and explicit solvation.

Room: Importkompaniet

Abstract: download

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Poster: P2-45

Author: Florian Rehak

Title: Differential Many-Body Cooperativity and Characterisation of Cu(I) TADF Complexes

Synopsis: Cooperative effects in various properties of Cu(I) TADF complexes are studied by means of differential many-body expansion.

Room: Importkompaniet

Abstract: download

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Poster: P2-46

Author: Ariadni Boziki

Title: Atomistic origins of the preferential stabilization of perovskite over non-perovskite phases of mixed cation lead halide perovskites

Synopsis: Mixed cation lead halide perovskites have attracted wide attention due to the possibility of tackling the problem of limited phase stability. Through a theoretical analysis of the phase stability of binary formamidinium (FA)-rich and cesium-rich FA/Cs and guanidinium (GUA)/FA mixtures as well as ternary Cs/GUA/FA mixtures, we propose a series of design principles for the synthesis of stable mixed cation lead halide perovskites that could be potential candidates for solar cell applications.

Room: Importkompaniet

Abstract: download

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Poster: P2-47

Author: Christof Holzer

Title: Prediction of properties for sizable molecular systems including spin-orbit effects

Synopsis: We will present robust yet efficient quasirelativistic algorithms and methods for calculating molecular properties of lifesized molecules

Room: Importkompaniet

Abstract: download

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Poster: P2-48

Author: Werner Dobrautz

Title: Compact numerical solutions to the two-dimensional repulsive Hubbard model obtained via non-unitary similarity transformations

Synopsis: Similarity transformation of the Hubbard Hamiltonian using a Gutzwiller correlator leads to a non-Hermitian effective Hamiltonian, which can be expressed exactly in momentum-space representation, and contains three-body interactions. We show that at optimal or near optimal strength of the Gutzwiller correlator, the similarity transformed Hamiltonian has extremely compact right eigenvectors, which can be sampled to high accuracy using the Full Configuration Interaction Quantum Monte Carlo method.

Room: Importkompaniet

Abstract: download

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Poster: P2-49

Author: Vincent Liégeois

Title: Magnetically-induced current density investigation in carbohelicenes and azahelicenes

Synopsis: In this poster, we investigate the magnetically-induced current (MIC) density for a variety of ortho fused polycyclic aromatic molecules at the density functional theory level with the gauge including magnetically induced current (GIMIC) method. With this method, the aromatic character of each ring in a homologous series of carbohelicenes with an increasing number of fused benzene rings is assessed and compared with other aromaticity criteria.

Room: Importkompaniet

Abstract: download

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Poster: P2-50

Author: Johann Mattiat

Title: Spectroscopy with RT-TDDFT

Synopsis: Real time time dependent density functional theory (RT-TDDFT) provides a natural way to obtain optical linear response functions. Applications to electric (absorption), magnetic (electric circular dichroism) and vibrational responses (Raman) are shown and discussed with special emphasis on origin invariance, different representations of the linear response functions, and the short time approximation in the vibrational case.

Room: Importkompaniet

Abstract: download

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Poster: P2-51

Author: Eugenio Vitale

Title: Embedding Schemes Applied to Strongly Correlated Systems

Synopsis: Two different embedding schemes are presented to study strongly correlated systems. In the first approach, an embedded FCI (full Configuration Interaction) is performed on top of the Distinguishable Cluster approximation (DCSD). In the second, a CEPA (Coupled-electron pair approximation) approach embedded in CISD (CI method with single and double excitations) is accomplished in order to investigate size-inconsistency issues in different open-shell transition metals.

Room: Importkompaniet

Abstract: download

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Poster: P2-52

Author: Leonard Reuter

Title: |Ψ|² Analysis: Extracting Valence Bond Information from Arbitrary Wave Functions

Synopsis: The valence bond methodology defines resonance structure weights to describe bonding in molecules. By analysing |Ψ|², these weights can be extracted from arbitrary wave functions.

Room: Importkompaniet

Abstract: download

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Poster: P2-53

Author: Michal Malček

Title: Combined DFT and spectroscopic study of biologically active Cu-, Ni-, Co-Quinolone complexes with phenantroline

Synopsis: Newly synthesized biologically active Cu, Ni, and Co complexes with selenadiazoloquinolone ligands have been studied by theoretical calculations and in situ EPR/UV-vis-NIR spectroelectrochemistry. Conformation analysis is compared with the experimentally obtained X-ray geometries. Non-relativistic and relativistic hyperfine coupling constants and g-tensors are presented.

Room: Importkompaniet

Abstract: download

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Poster: P2-54

Author: Fabian Mack

Title: Efficient Implementation of NMR Coupling Tensor Calculations

Synopsis: The calculation of NMR coupling tensors has been implemented into the program package TURBOMOLE. Coupling constants in molecules with about a hundred atoms can be calculated within hours. Timings for larger molecules are presented, employing the RI-K approximation or the seminumerical evaluation of the exchange. The computational effort can be reduced further by using smaller basis sets on atoms not directly involved in the couplings of interest.

Room: Importkompaniet

Abstract: download

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Poster: P2-55

Author: Josene Toldo

Title: Is the Excited State Aromaticity a Driving Force for Planarization of Dibenzannelated 8pi-Electron heterocycles?

Synopsis: Dibenzannelated heterocyclic compounds with central 8pi-electrons ring are found in a range of different applications. The lowest excited states of such compounds can be aromatic according to Baird’s 4n rule. Yet, when is that the case? We use quantum chemical calculations to evaluate if and when changes in excited state geometries are driven by changes in aromaticity.

Room: Importkompaniet

Abstract: download

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Poster: P2-56

Author: Christopher Ehlert

Title: An efficient first principles method for molecular pump-probe NEXAFS spectra: Application to thymine and azobenzene

Synopsis: Pump-probe near edge X-ray absorption fine structure (PP-NEXAFS) is a powerful analytical tool to investigate molecules in the gas phase or adsorbed on surfaces. We propose an efficient, first principles method based on density functional theory in combination with the transition potential and Δ-SCF methodology (TP-DFT/Δ-SCF), to compute molecular ground state and PP-NEXAFS spectra. We apply the method to O-K-edge of thymine, and the N-K-edge of trans- and cis-azobenzene.

Room: Importkompaniet

Abstract: download

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Poster: P2-57

Author: George Trenins

Title: Mean-Field Dynamics of Curvilinear Centroids: Tackling the Curvature Problem

Synopsis: We present a new path-integral method for approximating quantum dynamics in condensed-matter systems. Our method is based on the mean-field dynamics of curvilinear centroids, which avoids the common problems encountered by popular path-integral approaches in simulations of infra-red absorption spectra. We demonstrate that the new method performs well over a broad range of temperatures in test systems varying from two-dimensional models to q-TIP4P/F liquid water and ice.

Room: Importkompaniet

Abstract: download

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Poster: P2-58

Author: David Mester

Title: Reduced-scaling correlation methods for the excited states of large molecules

Synopsis: A framework for the reduced-scaling implementation of excited-state correlation methods is presented. The sizes of the resulting compact domains are further decreased utilizing our reduced-cost techniques. The results of benchmark calculations performed at the ADC(2) level are presented, and it is demonstrated that the speedups achieved are significant even for systems of smaller than 100 atoms, while the errors introduced by our approximation are highly acceptable.

Room: Importkompaniet

Abstract: download

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Poster: P2-59

Author: Tong Jiang

Title: Frequency Domain Density Matrix Renormalization Group Algorithms for Dynamical Correlation Function of Molecular Aggregates at both Zero and Finite Temperature

Synopsis: This poster will present the frequency domain DMRG algorithms, including the correction vector approach and the Chebyshev expansion approach at both zero and finite temperature for Holstein model to calculate the dynamical correlation function of molecular aggregates.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-60

Author: Sebastian Mai

Title: Ultrafast Intersystem Crossing in Third-Row and Fifth-Row Transition Metal Complexes

Synopsis: Based on extensive nonadiabatic dynamics simulations using the Surface Hopping including Arbitrary Couplings (SHARC) method, we compare the ultrafast intersystem crossing mechanisms of two prototypical transition metal complexes, the third-row complex [Fe(CN)4 (2,2’-bipyridine)]2− and the fifth-row complex [Re(CO)3 (imidazole)(phenanthroline)]+. It was found that in the Re complex electronic ISC and nuclear-relaxation-driven ISC occur on different time scales, unlike in the Fe complex.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-61

Author: Sundeep Popat

Title: Constant-Uncertainty Molecular Dynamics. A Practical Method for Approximating Quantum Dynamics?

Synopsis: Constant-uncertainty molecular dynamics (CUMD) has been proposed as a “simple and efficient” method in which quantum effects can be incorporated into classical molecular dynamics simulations. The method has been shown to give better results than ring-polymer molecular dynamics (RPMD) for one-dimensional test systems. We analyse the method, discuss the problems that arise from it and consider the potential use of the first step of the method (momenta rescaling of RPMD beads).

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-62

Author: Maikel Ballester

Title: A comparative study of CdH and N2 systems in their ground electronic states between Hylleraas, Varandas and Aguado-Paniagua potentials

Synopsis: The evolution in the field of diatomic potential energy curves is here evaluated, comparing current methods with those proposed more than 80 years ago. For such, we have chosen analytic representations by Hylleraas, Varandas and Aguado-Paniagua. For comparisons, the diatomic systems CdH and N2 both in their respective ground electronic states were selected. Ab initio electronic energies calculated at multireference configuration interaction (MRCI) using AVXZ (X = Q,5,6) basis set were employed

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-63

Author: Anna Spyszkiewicz

Title: Nonadiabatic Relativistic and QED Correction to the Dissociation Energy of the Hydrogen Molecule Isotopologues

Synopsis: We search for discrepancies between highly accurate spectroscopic measurements and theoretical predictions based on QED, in order to discover new effects or even new interactions which might result in the developement of the Standard Model. We will present the latest advances in calculation reaching the subMHz level for the dissociation energy of molecular hydrogen isotopoloques.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-64

Author: Sang-Yeon Hwang

Title: Scaffold-Based Molecular Design Using a Graph Generative Model

Synopsis: We developed a scaffold-based graph generative model. Our model extends a molecular scaffold into new molecules by sequentially adding atoms and bonds. Our approach is applicable in situations where one wants to find the right combination of functional groups that optimizes the functionality of a desired scaffold.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-65

Author: Andreas Irmler

Title: Insights into basis-set convergence from diagrammatic decomposition

Synopsis: An analysis of different diagrammatic contributions to the CCSD energy leads to a basis-set extrapolation scheme for molecular and solid-state systems.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-66

Author: Paweł Tecmer

Title: New insights into the ground and excited states properties of ThO and ThS from 4-component theories

Synopsis: We present a comprehensive relativistic coupled cluster study of the electronic structures of the ThO and ThS molecules in the spinor basis. Specifically, we use the single-reference coupled cluster and the multi-reference Fock Space Coupled Cluster methods to model their ground and electronically-excited states.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-67

Author: Merced M. Montero-Campillo

Title: Reinforcing chalcogen bonds through alkaline-earth bonds

Synopsis: G4 calculations show that the strength of chalcogen interactions is dramatically enhanced by the presence of alkaline-earth bonds. Cooperativity between these non-covalent interactions is studied exploring different complexes between chalcogen derivatives, alkaline-earth derivatives and N-bases. In terms of binding energies, chalcogen bonds can be enhanced by one order of magnitude. This is due to the interplay of all non-covalent interactions involved, including secondary hydrogen bonds.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-68

Author: Andrej Antalík

Title: The Peculiar Case of Oxo-Mn(Salen)

Synopsis: How do the active space composition, basis set and dynamic correlation affect the character of the ground state of oxo-Mn(Salen) molecule?

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-69

Author: Serguei Feskov

Title: Modeling multistage ultrafast photoinduced electron transfer in complex environments with multiple relaxation timescales

Synopsis: We report an extension of our previous approach [S.V. Feskov, A.I. Ivanov, J. Chem. Phys. 2018] for theoretical description of ultrafast multistage photoreactions involving multiple sequential transfer of electron between several redox centers in a molecular compound. The extension allows taking into account complex dynamics of dielectric relaxation in vicinity of the redox sites, which is important for studying ultrafast reactions in non-Debye solvents or biological environments.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-70

Author: Geórgia M. A. Junqueira

Title: An experimental and Molecular Approach of the Anticancer Action of RGD-Peptide Lunasin

Synopsis: Lunasin is a cancer-preventive peptide isolated from soybean, wheat, barley and other seeds. This compound contains 43 amino acid residues with a cell adhesion motif constituted by arginine-glycine-aspartic acid (RGD) and a carboxylic acid tail of nine aspartic (D) acids. Both experimental and computational analyses were carried out to study chemical and physical interactions between lunasin and integrins.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-71

Author: Alexey Arbuznikov

Title: Local hybrid exchange-correlation functionals based on the static dielectric function

Synopsis: The wide success of Kohn-Sham density functional theory strongly depends on the approximate exchange-correlation functional used. In this work we further develop local hybrid functionals, where the exact-exchange admixture is position-dependent (governed by a local mixing function, LMF). A new LMF is built as an inverse of the static dielectric function. The latter is based on the local ionization potential. Preliminary validation studies yield promising results for the thermochemical kinetics.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-72

Author: Stig Rune Jensen

Title: MRChem, a quantum chemistry code with unlimited basis sets. Parallelization and scaling

Synopsis: MRChem completely avoids the use of traditional Gaussian type basis sets. Instead the real space is subdivided into smaller regions, based on multiresolution analysis. In our present implementation, systems with hundreds of electrons can be described. The intrinsic adaptation of the grid to the actual functions, leads directly to a decrease of computation time for long range interactions. We present the parallelization strategy adopted, and examples of scalability.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-73

Author: Jil Ludovicy

Title: Full Wave Function Optimization of Transition Metal Compounds with Quantum Monte Carlo

Synopsis: Dissociation energies of transition metal dimers have been calculated at multi-reference diffusion Monte Carlo level. The Jastrow, CI, and MO parameters of Jastrow-CAS wave functions are optimized with respect to the variational energy. Fully optimized wave functions are necessary to obtain excellent agreement with the experiment.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-74

Author: Jan Brandejs

Title: Relativistic coupled clusters externally corrected by four-component DMRG

Synopsis: There are three essential problems in computational relativistic chemistry: electrons moving at relativistic speeds, degenerate energy levels and dynamical correlation. Current methods are capable of solving systems with one or two of these issues. However, all the three effects are present in heavier transition metal compounds, lanthanides and actinides with open d or f shells. We combine relativistic coupled clusters with DMRG method in order to address this challenging class of molecules.

Room: Kjøpmannskontoret

Abstract: download

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Poster: P2-75

Author: Paul Clabaut

Title: Free energy of adsorption evaluation at the metal/liquid interface

Synopsis: Presentation of two methodological development in the domain of the solvation at the solid/liquid interface. The first is a scheme, based on a mixed QM and MM approach to evaluate the adsorption free energy of any molecule at the interface. The second is a force-field, used to precisely describe metal/water interactions. It is able to reproduce adsorption features of water on 10 different metallic surfaces: 100 and 11 facets of Pt, Au, Ag, Cu and Pd.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-76

Author: Julien Roulet

Title: Efficient geometric integrators for nonadiabatic quantum dynamics. II. The diabatic representation

Synopsis: The first- and second-order split-operator algorithms are widely used integrators for solving the time-dependent Schrödinger equation. Higher-order split-operator based integrators are not commonly used because they are thought to be inefficient due to the large number of Fourier transforms they require. Here, we show that higher-order integrators obtained by composing the second-order split-operator algorithm can be much more efficient if higher accuracy is desired.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-77

Author: Karen Oda Hjorth Dundas

Title: A computational protocol for calculation of IR and Raman spectra for solvated systems

Synopsis: We here present a computational protocol for how to analytically determine IR and Raman spectra for molecules in solution.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-78

Author: S. Karl-Mikael Svensson

Title: Classical Wigner model based on a Feynman path integral open polymer

Synopsis: The classical Wigner model is a way of accounting for quantum mechanical effects when studying the dynamics of molecular systems. In this model you initially have a quantum mechanical phase space distribution, called a Wigner function, and propagate it forward in time by classical mechanics. In this project small systems are studied, and the initial Wigner function is sampled by the use of Monte Carlo on an imaginary time Feynman path integral open polymer.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-79

Author: Beatriz von der Esch

Title: Free energy reaction profile of the desuccinylaiton catalyzed by Sirtuin 5

Synopsis: The desuccinylation reaction by sirtuin 5 poses important challenges for a quantum-chemical study. One major issue is that most schemes to characterize enzymatic reactions strongly depend on the chosen educt conformation. Here, we utilize machine learning to identify suitable start-frames and relevant structural features for the initial step of the desuccinlyation. Subsequent umbrella sampling and the weighted histogram analysis method were employed to compute the free energy reaction profile.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-80

Author: Pratip Chakraborty

Title: Insights into S2 population trapping of uracil using trajectory surface hopping dynamics

Synopsis: In order to understand how the dynamics of uracil is influenced by the underlying electronic structure theory, we have performed the excited state dynamics of uracil using on-the-fly trajectory surface hopping method on potential energy surfaces calculated at different electronic structure theory levels to investigate the effect of the barrier on S2 state on the decay dynamics.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-81

Author: Katarzyna Jakubowska

Title: NMR parametrs of Hg - H2O complex: relativistic four-component calculations.

Synopsis: Main objective of the project was to calculate dependencies of nuclear shielding constants and indirect spin-spin coupling constants on geometric parameters of mercury atom and water molecule complex with the use of relativistic four-component DFT method. Moreover, potential energy surface of the complex was studied by means of relativistic CCSD(T) and DFT methods.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-82

Author: Attila Bende

Title: The influence of the metal-ligand charge transfer effects on the structural stability and the strength of the spin-orbit coupling in Ni(II)-based metal-ligand complexes

Synopsis: The structural stability, charge transfer effects and the strength of the spin-orbit couplings in Ni(II)-ligand complexes with square-pyramidal and octahedral coordination, considering porphyrin- and diketo-pyrphyrin-based four-coordination macrocycles as planar ligands as well as pyridine, pyrrole and mesylate anion molecular groups as vertical ligands have been studied at DFT level of theory.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-83

Author: Christoph Bauer

Title: Inter- and Intramolecular Hydrogen Bond Strengths Modeled with Quantum Chemistry

Synopsis: I present the computation of both inter- and intramolecular hydrogen bond (IMHB) strengths. Quantum chemical (QC) calculations including free energy and solvation contributions are conducted for (i) intermolecular hydrogen bonds (ii) IMHB-forming compounds. The computed Delta G values in solution for intermolecular HB show a root mean square error (RMSE) to the experiment of 4.25 kJ/mol. The IMHB Delta G values in solution yield a RMSE to the experiment of 5.51 kJ/mol.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-84

Author: Kresimir Rupnik

Title: Probing Unusual Hidden Electron Dynamics in Molecules of Biomedical Interest Using Soft PPS Radiation Signatures (RS) in the Framework of Attomechanics Models

Synopsis: We study causal relations between electron attodynamics and interacting radiation by measuring characteristic electron Radiation Signatures using PPS High Magnetic Field and attomechanics modeling. Scientifically important question here is: can these methods probe electrons during protein synthesis and activities. Some of our most important findings include previously unseen electron dynamics: we can separate signatures from previously indistinguishable proteins and hidden-electron spin-flips.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-85

Author: Jun Shen

Title: Efficient Implementation and Applications of the Doubly Electron-Attached and Doubly Ionized Equation-of-Motion Coupled-Cluster Methods

Synopsis: We report our progress in the development, implementation, and applications of the doubly electron-attached (DEA) and doubly ionized (DIP) equation-of-motion coupled-cluster (EOMCC) methods with up to 4-particle–2-hole and 4-hole–2-particle excitations, treated fully or with active orbitals. Our new DEA and DIP EOMCC codes with high-order excitations allow us to handle challenging multi-reference problems, including singlet–triplet gaps in organic biradicals, with unprecedented accuracies.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-86

Author: Iwona Majewska

Title: Crossover from the quantum to the quasiclassical regime in photodissociation of ultracold molecules

Synopsis: Theoretical quantum model of photodissociation, based on the Fermi golden rule, was successfully applied to explain the photodissociation reaction of the ultracold strontium dimer. It was extended to include the external magnetic field influence. The crossover from the quantum to the quasiclassical regime with increasing kinetic energy of the fragments was studied. It was proven that the quasiclassical model fails for some state configurations, because of the nuclear spin statistics effect.

Room: Arbeidskontoret-1+2

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Poster: P2-87

Author: Susannah Bourne Worster

Title: Structure and efficiency in bacterial photosynthetic light harvesting

Synopsis: Lindblad operators are used to model the multiple processes governing energy transport through a photosynthetic antenna network, with a particular focus on capturing the interaction with light and with a vibrational bath in a detailed and realistic manner. The model is applied to a natural antenna network from purple bacteria and to illustrative unstructured networks, with surprising implications for the design of artificial light-harvesting devices.

Room: Arbeidskontoret-1+2

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Poster: P2-88

Author: Johan E. Runeson

Title: Spin-mapping approach to nonadiabatic dynamics

Synopsis: We present a trajectory-based method for simulating nonadiabatic dynamics in molecular systems with two coupled electronic states. Is employs a mapping to a spin-1/2 coherent state and shares many features with the Meyer-Miller-Stock-Thoss mapping, with the important difference that it requires no additional projections onto the space of physical states. The results improve on both Ehrenfest and MMST calculations for various spin-boson problems without adding any additional complexity.

Room: Arbeidskontoret-1+2

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Poster: P2-89

Author: Konstantin Gaul

Title: Flexible toolbox for calculation of relativistic properties with two- component densities

Synopsis: A general formulation of relativistic one-electron properties in terms of density functions is presented, which allows for customized definition of operators within a generic two-component property module. An implementation within a two-component zeroth order regular approximation framework for the use with a modified version of the Turbomole program package is outlined. Within this implementation arbitrary relativistic properties can be calculated.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-90

Author: Eléonor Acher

Title: A consistent molecular model to predict the behavior of tetravalent actinides from thorium to berkelium.

Synopsis: We present here the development of a force-field for the An(IV) series from Th(IV) to Bk(IV) in water. As the reliability of the classical molecular dynamics simulations entirely relies on the force-field quality, we first present the state-of-the-art ab initio parameterization methodology developed in this work. The first trends in the An(IV)-H2O interaction for the series, obtained by classical molecular dynamics simulations, are then presented.

Room: Arbeidskontoret-1+2

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Poster: P2-91

Author: Daniele Loco

Title: Hybrid QM/MM Dynamics of Complex Systems within the AMOEBA Polarizable Embedding

Synopsis: A review of the recently implemented hybrid QM/MM MD approach within the AMOEBA polarizable embedding is given. Details about the new capabilities, concerning periodic boundary conditions and new multiple time scale integrators for the classical equations of motion, are presented. New case studies are presented, involving molecular systems embedded in complex environments, such as DNA or protein matrices.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-92

Author: Seonghoon Choi

Title: Efficient geometric integrators for nonadiabatic quantum dynamics in the adiabatic representation

Synopsis: Geometric integrators of the Schrödinger equation conserve exactly many invariants of the exact solution. We present integrators of arbitrary order of accuracy in the time step based on compositions of the Crank-Nicolson method applicable to both separable and nonseparable Hamiltonians and, in particular, to the nonadiabatic molecular Hamiltonian in the adiabatic representation. These integrators are exactly unitary, symplectic, symmetric, time-reversible, stable, and energy conserving.

Room: Arbeidskontoret-1+2

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Poster: P2-93

Author: V. S. Sandeep Inakollu

Title: A computational investigation of the effects of solvent-induced electric fields on vibrational frequency shifts

Synopsis: We benchmarked the computational vibrational spectroscopic methods including normal mode analysis (NMA) and fast Fourier transform dipole autocorrelation function (FT-DAC). We demonstrated the advantages of the FT-DAC method for flexible and anharmonic systems. We have investigated the effects of solvent-induced electric field on vibrational frequency shifts, and linear correlation was found. We showed the importance of including explicit polarisations at the QM/MM simulations.

Room: Arbeidskontoret-1+2

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Poster: P2-94

Author: Maricris Mayes

Title: The Role of Non-Covalent Interactions in the Self-Assembly of Aromatic Peptide Nanotubes

Synopsis: This work confirms the role of π-π stacking, electrostatic, and dispersion forces in the stabilization between tryptophan-tyrosine dipeptide units, and likely drive aggregation of self-assembled structures from peptide-based molecular frameworks.

Room: Arbeidskontoret-1+2

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Poster: P2-95

Author: Ivana Nikšić-Franjić

Title: The exciting aqueous chemistry of the simplest radical – proton-coupled electron transfer in the reactions of hydrogen atom

Synopsis: The computations indicate a possibility that the mechanism of proton-coupled electron transfer (PCET) may occur in the simplest possible setting – in the reactions of the hydrogen atom. We report experimental and theoretical studies on the hydrogen atom in reactions with three haloacetates (chloroacetate, bromoacetate, and iodoacetate), and 5-bromouracil, which take place in non-buffered and buffered aqueous solutions.

Room: Arbeidskontoret-1+2

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Poster: P2-96

Author: Eite Tiesinga

Title: Elastic rate coefficients for Li + H2 collisions in the calibration of a cold-atom vacuum standard

Synopsis: Ongoing efforts at the National Institute of Standards and Technology in creating a cold-atom vacuum standard device have prompted theoretical investigations of atom-molecule collision processes that characterize its operation. Such a device will operate as a primary standard for the ultrahigh-vacuum and extreme-high-vacuum regimes. This device operates by relating loss of ultracold lithium atoms from a conservative trap by collisions with ambient atoms and molecules to the background density an

Room: Arbeidskontoret-1+2

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Poster: P2-97

Author: Manish Thapa

Title: Nonadiabatic quantum transition-state theory in the golden-rule limit

Synopsis: We have recently developed a new golden-rule quantum transition-state theory (GR-QTST) to compute reaction rates in complex multi-dimensional systems . Our theory relies on constrained path-integral sampling of instanton-like paths, and hence predicts rates accurately for both harmonic and anharmonic model systems even in the deep tunneling regime. We show that our theory can be employed to study systems that exhibit multiple transition states, and is applicable to study reactions in solution.

Room: Arbeidskontoret-1+2

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Poster: P2-98

Author: Magnar Bjorgve

Title: Periodic MRChem

Synopsis: MRChem is a numerical real-space code for molecular electronic structure calculations within the self-consistent field (SCF) approximation of quantum chemistry, Hartree-Fock and Density Functional Theory. MRChem uses a multiwavelet (MW) basis, and are used in quantum chemical calculations due to their mathematical properties, such as, error control and low scaling. Here we show how MRChem is working on periodic systems.

Room: Arbeidskontoret-1+2

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Poster: P2-99

Author: Shmuel Zilberg

Title: Rydberg bonding - the non-valence long-range covalent bond

Synopsis: Non-valence Rydberg bonding was studied computationally for the different diaza-derivatives of cyclohexane and other polycycles. The optimal position of N-centers for the Rydberg binding is 1,4-diaza location. The energy of N-N Rydberg bond could reach 0.9eV. Calculations show both thermodynamic and a kinetic stabilization for these structures with Rydberg N-N bond.VB analysis of the 3s-3s AOs binding between two N-atoms shows the dominant covalent character of the Rydberg N-N bond.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-100

Author: Ria Broer

Title: Unravelling the Nature and the Timescale of the Dielectric Constant for Organic Semiconductors

Synopsis: A way to improve the efficiency of organic photovoltaic devices is to use materials with a high dielectric constant. A good strategy to this is to use ethylene glycol side chains. We present a multiscale computational scheme to calculate the electronic, dipolar and induced contributions to the dielectric constant. We decompose the dielectric contributions into molecular fragments, allowing us to clearly pinpoint their origin. Also, our results for the first time unravel the response timescales.

Room: Arbeidskontoret-1+2

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Poster: P2-101

Author: Takatoshi Fujita

Title: Development of the Fragment-Based GW+Bethe-Salpeter Equation Method for Applications to Organic Materials

Synopsis: We present a large-scale GW implementation based on the fragment molecular orbital method. The implementation is based on the fragmentation approximation of the polarization function and the combined GW and Coulomb-hole plus screened exchange approximations for self-energies. The fragment-based GW is demonstrated by applications an organic semiconductor thin film and a donor/acceptor interface structure.

Room: Arbeidskontoret-1+2

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Poster: P2-102

Author: Geórgia M. A. Junqueira

Title: The Role Played by Vitamin A as a Probe in Milk: A Vibrational and Electronic Study

Synopsis: The vibrational spectra were obtained to retinol, retinyl ester, retinol acetate and retinal. In order to investigate Time-Resolved Fluorescence measures of retinol in milk, lifetime decays were carried out, by means of TD-DFT approach. Once vitamin A is a naturally spectroscopic probe in milk, our findings contribute to understanding its profile in different environments, either to differentiate types of milk or to assess the quality of dairy products.

Room: Arbeidskontoret-1+2

Abstract: download

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Poster: P2-103

Author: Lei Tan

Title: Structures of CdSe and CdS nanocluster by ab initio random structure searching

Synopsis: The properties of colloidal semiconductor quantum dots (QDs) continue to stimulate a lot of interest in a wide variety of field including materials, photonics, energy applications etc. Over the last few years, there has been a lot of interest in ultra-small QDs that do not follow the usual nucleation- and-growth model during the synthesis - so-called Magic-Sized Clusters (MSCs). These MSCs have an advantage of being mono-diapers systems with a number of unusual optical properties including tempe

Room: Arbeidskontoret-1+2

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Poster: P2-104

Author: Dmitry Fedorov

Title: Quantum-mechanical relations between polarizabilities and geometric properties of atoms

Synopsis: We derive quantum-mechanical relations between atomic polarizabilities and atomic van der Waals radii and volumes by means of the quantum Drude oscillator model. It is shown that the discovered quantum relations accurately capture properties of real vdW-bonded atomic systems throughout the periodic table. Moreover, the revealed relations simplify the parametrization of vdW-interatomic potentials and increase the accuracy of computational models for intermolecular interactions.

Room: Arbeidskontoret-1+2

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Poster: P2-105

Author: Jun Haruyama

Title: Definition of Electrode Potential from Density Functional + Implicit Solvation Theory

Synopsis: Electrode potential is a general concept, in electrochemistry, which governs the charge transfer reactions such as ion insertion/extraction and reduction-oxidation at electrode/solution interfaces; the electrode potential should be appropriately included in the computational model. In this study, we consider how the standard hydrogen electrode potential, which is the equilibrium potential of the charge transfer reaction of H+/H2, is theoretically evaluated.

Room: Arbeidskontoret-1+2

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Poster: P2-106

Author: Alexandra Freidzon

Title: Local or Nonlocal? A Multireference Study of Charge and Exciton Transport in Organic Semiconductors

Synopsis: We propose a computational procedure based on CASSCF/XMCQDPT calculation to track the charge or exciton transfer path in organic semiconductors and to elucidate the role of hard and soft vibrational modes in the hopping process. The examples of typical electron- and hole-transporting materials Bebq2 and α-NPD are considered.

Room: Arbeidskontoret-1+2

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Poster: P2-107

Author: Drahomír Hnyk

Title: Chalcogens Outerly and Innerly Functionalize Various Boron-Based Cages. Molecular Structures of the Resulting Heteroboranes Determined Using Electron Diffraction and Computational Protocols

Synopsis: This presentation summarizes a joint electron diffraction/computational studies of various chalcogenboranes with chalcogen atoms that are part of a cluster or that substitute terminal hydrogen atoms. Electron scattering experiments were carried out in Edinburgh (UK), Bielefeld (Germany), and Oslo (Norway). The molecular structure determinations are based on the theory of electron scattering. Computations of molecular geometries and shielding tensors serve as additional refinement conditions.

Room: Arbeidskontoret-1+2

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Poster: P2-108

Author: Jan P. Unsleber

Title: Strategies and Requirements for the Automated Exploration of Complex Chemical Reaction Networks

Synopsis: A discussion of strategies for the automated exploration of complex chemical reaction networks, and requirements for a software implementing these strategies using our own approach as an example. Key steps in the exploration of networks, such as error control, as well as the final visualization and interpretation of generated data will be touched upon.

Room: Arbeidskontoret-1+2

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Poster: P2-109

Author: Thomas Weymuth

Title: Error-Propagation by Increments

Synopsis: In order to quantify the uncertainty of quantum chemical results, we propose an approach for the archigenesis of error estimates. The approach is based on a many-body expansion in terms of embedded molecular fragments. These fragments are chosen such that accurate reference calculations are feasible. The error estimate obtained from these calculations is then propagated to the full molecule.

Room: Arbeidskontoret-1+2

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Poster: P2-110

Author: Felix Witte

Title: Understanding switchable processes in supramolecular systems

Synopsis: Molecular machines have been widely popularized by the 2016 awarded Nobel prize in chemistry. The underlying mechanisms working the machines are usually dominated by intramolecular dispersive interactions difficult to assess experimentally. Here, we study the switching mechanisms within two rotaxanes functionalised by redox-active TTF (tetrathiafulvalene) units using DFT-based approaches.

Room: Arbeidskontoret-1+2

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Poster: P2-111

Author: Jindrich Fanfrlik

Title: Noncovalent Interactions of Boron Clusters

Synopsis: Boron clusters are group of compounds with unusual noncovalent interactions, which include dihydrogen and sigma-hole bonds. The ability of heteroboranes to form strong sigma-hole interactions might be attributed to the multicenter bonding. It breaks the classical electronegativity concept and results in highly positive sigma-holes on heteroatoms. We have observed the various types of sigma-hole interactions of heteroboranes in the corresponding crystal packings.

Room: Arbeidskontoret-1+2

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Poster: P2-112

Author: Rui Pedro Pimenta Neves

Title: Computational engineering of efficient enzyme catalysts for biodesulfurization of sour crude oil through 4S pathway

Synopsis: The 4S metabolic pathway of bacteria strain IGTS8 is regarded as an efficient green alternative to current methods of sour crude oil desulfurization. Out of the 4 enzymes in the pathway, the flavin monooxygenase DszC and the desulfinase DszB are identified bottlenecks. We have been combining quantum mechanics/molecular mechanics and molecular dynamics simulations to study their reaction mechanism and develop rational enzyme engineering protocols to improve their industrial applicability.

Room: Arbeidskontoret-1+2

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Poster: P2-113

Author: Alberto Baiardi

Title: Efficient quantum dynamics with the time-dependent density matrix renormalization group

Synopsis: In the present contribution, we generalize the density matrix renormalization group (DMRG) algorithm to the simulation of time-dependent processes. The resulting theory is applied to the simulation of both nuclear and electronic dynamics, possibly coupled together, of molecules with several dozens of degrees of freedom. We assess the accuracy of the simulations by comparison with state-of-the-art experimental measurements obtained from time-resolved spectroscopic techniques.

Room: Arbeidskontoret-1+2

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Poster: P2-114

Author: Mirko Vanzan

Title: A multiscale computational approach to investigate small gold nanoclusters optical features in solution

Synopsis: TDDFT calculations were performed on small Au25 nanoclusters, finding that different orientations of the organic ligands can give sensible modification of the metallic kernel. Metadynamics simulations were also performed on three different [Au25(SR)18]q double clusters systems, finding the tendency in forming cluster aggregates depends on the organic chains lengths and structures but is weakly affected by the nanoclusters charge.

Room: Arbeidskontoret-1+2

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Poster: P2-115

Author: Vincent Montigaud

Title: Modulation of Single-Molecule Magnet Properties: a Theoretical Investigation

Synopsis: This work focuses on the computational investigation of the Single-Molecule Magnet properties, in two lanthanide(III)-based molecular systems, using wavefunction-based methods. In both cases, the modulation of the magnetic properties is observed through reversible hydro- and/or redox- mechanisms.

Room: Arbeidskontoret-1+2

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Poster: P2-116

Author: Luisa Stelter

Title: Theoretical Studies on the Hydroaminoalkylation of Alkenes with Primary and Secondary Amines

Synopsis: The hydroaminoalkylation of alkenes catalyzed by transition-metal complexes represents an efficient method for the synthesis of functionalized amines. In this contribution we investigate the unexpected different reaction behavior of primary and secondary amines by calculating reaction pathways including thermodynamic data with hybrid DFT. As a result, the non-possible use of methylamine in the laboratory, unlike dimethylamine, can now be linked to competing reactions to the catalytic cycle.

Room: Arbeidskontoret-1+2

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Poster: P2-117

Author: Thomas Teusch

Title: Water Oxidation on WO3(001) – An Embedded Cluster Study

Synopsis: In this contribution we use embedded cluster models to study ground and charge transfer states of a water molecule on WO3(001) with multireference methods in the relevant degrees of freedom. We applied state-of-the-art machine learning methods like residual connections to fit the resulting PES.

Room: Arbeidskontoret-1+2

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Poster: P2-118

Author: Youcef Yousfi

Title: Understanding the mechanism and regioselectivity of the copper and Ruthenium catalyzed 1,3-dipolar cycloaddition of azido ribose derivative with alkyne. A DFT study

Synopsis: 1,2,3 Triazoles constitute a family of compounds known for their momentous and valued biological activities. Their biomedical applications include the treatment of tumors, diabetes, microbial and fungal infections and inhibition of HIV protease. In our study, in the fild of click chemistry both the uncatalyzed and the CuAAC and RuAAC reactions were modeled and discussed in terms of relative energies obtained from quantum-mechanical calculations performed at the B3LYP/6-31G(d) level of theory.

Room: Arbeidskontoret-1+2

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Poster: P2-119

Author: Ayaki Sunaga

Title: Using effective QED potentials in molecular calculations

Synopsis: Improved computational power and methodology nowadays allow highly accurate electronic structure calculations including both relativistic and electron correlation effects. A next challenge for increased accuracy is the inclusion of the effects of quantum electrodynamics (QED). In this work, we report the first implementation of effective QED potentials in a program for all-electron molecular relativistic calculations, DIRAC. In our presentation, we show some results of sample calculations.

Room: Arbeidskontoret-1+2

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Poster: P2-120

Author: Himadri Pathak

Title: Time-dependent Optimized Coupled-cluster Framework for Laser-driven Multielectron Dynamics

Synopsis: This contribution deals with the formulation and implementation of a gauge invariant time- dependent optimized coupled-cluster (TD-OCC) method where both orbitals and amplitudes are time-dependent for the study of intense laser-induced multielectron dynamics. The TD-OCC method is a polynomial cost-scaling substitute to the rigorous but factorial cost-scaling multiconfiguration time-dependent Hartree-Fock method (MCTDHF).

Room: Arbeidskontoret-1+2

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Poster: P2-121

Author: Emmanuel Giner

Title: A Density-Based Basis Set Correction For Wave Function Theory

Synopsis: We report the extension of a recently proposed [1] universal density-based basis set incompleteness correction that can be applied to any wave function method, together with its first numerical application on molecular systems. The present correction, which appropriately vanishes in the complete basis set (CBS) limit, relies on short-range correlation density functionals and allows us to obtain near CBS correlation energies for the G2 molecular set.

Room: Arbeidskontoret-1+2

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Poster: P2-122

Author: Rachael Al-Saadon

Title: Spin-orbit coupling from multistate CASPT2

Synopsis: We report an approach to compute spin–orbit coupling within the extended multistate second-order multiconfigurational perturbation theory (XMS-CASPT2). Our approach is based on the state interaction method, in which both diagonal and off-diagonal elements of the spin–orbit matrix are computed at the CASPT2 level. It enables analysis of chemical processes that occur as a result of a change in spin multiplicity, such as photocatalysis and those involving intersystem crossing.

Room: Arbeidskontoret-1+2

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Poster: P2-123

Author: Yoshiyuki Yamamoto

Title: Scaling relation between adsorption energies of oxygen reduction reaction intermediates at defective TiO2 surfaces

Synopsis: Enhancing the oxygen reduction reaction is a major topic of electrocatalysis research. The maximal enhancement is, however, hampered by the universal scaling among adsorption energies of intermediates. Thus, violating the relation is an important issue in catalyst design. Our DFT calculations suggest that the relation is violated on defective TiO2 when the adsorbent has a bond with a lattice oxygen atom. Our study paves the way for overcoming the activity limit that conventional catalysts have.

Room: Arbeidskontoret-1+2

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Poster: P2-124

Author: Tomilola Joseph Ajayi

Title: Computational modelling of pH Responsive Nano-valves in Controlled-release System.

Synopsis: A category of nano-valves system containing the cucurbit[7]uril ring on a stalk tethered to the pores of mesoporous silica nanoparticles(MSN) is theoretically and computationally modeled.

Room: Arbeidskontoret-1+2

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Poster: P2-125

Author: Elena Bocharnikova

Title: Combined Theoretical and Experimental Study of Bisphenol A Photolysis

Synopsis: Quantum-chemical methods using the theory of intramolecular photophysical processes have been used to interpret the spectral-luminescent properties of BPA (Bisphenol A) in hexane and toluene, to establish the orbital nature of photodissociative states and the mechanism of C5–C8 and C8–C11 bonds splitting. The effect of excitation energy on the efficiency of photoreactions has been found.

Room: Arbeidskontoret-1+2

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Poster: P2-126

Author: Wei Wang

Title: Internal friction in protein systems: a physical insight from simplified models

Synopsis: nternal friction of protein systems is a problem without clear physical understanding. We described the emergence of internal friction in dynamic systems based on the formalism of Langevin equation. Our results successfully explained various features of internal friction in protein systems.

Room: Arbeidskontoret-1+2

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Poster: P2-127

Author: Nadav Genossar

Title: Ab initio Calculations of the Rotational Spectrum of Hydroperoxy-acetaldehyde

Synopsis: A high accuracy ab initio prediction of the rotational spectrum of CHO-CH2-OOH, hydroperoxy-acetaldehyde, a keto-hydroperoxide (KHP) was performed. This species is believed to be produced under the ozonolysis of ethylene. The geometry optimization was performed at the all-electron CCSD(T)/cc-pCVQZ level of theory, and anharmonic effects were incorporated through VPT2 calculations using the frozen core CCSD(T)/ANO0 level of theory.

Room: Arbeidskontoret-1+2

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Poster: P2-128

Author: Soumi Haldar

Title: Multilayer Approach to the IP-EOM-DLPNO-CCSD Method: Theory, Implementation, and Application

Synopsis: We present a multilayer implementation of the EOM-CCSD for the computation of ionization potentials of molecules in the presence of their environment. The method uses local orbitals to partition the system into a number of hypothetical fragments and treat different fragments at different levels of theory. This approach significantly reduces the computational cost with a systematically controllable accuracy and is equally applicable to describe the environmental effect of both bonded nature.

Room: Arbeidskontoret-1+2

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Poster: P2-129

Author: Yu-Jane Sheng

Title: Hybridization of Lipids to Monolayer and Bilayer Membranes of Triblock Copolymers

Synopsis: The influences of the fraction of loop-conformation (monolayer, bilayer, and mixed structure) on the structural, mechanical, and transport properties of the membrane were obtained. The phase behavior of the hybrid membrane was studied. The transition from the mixing state (homogenous distribution of lipids) to the demixing state (lipid-rich domain) was clearly identified. The structural incompatibility between triblock copolymers and lipids can lead to phase separation in hybrid membranes.

Room: Arbeidskontoret-1+2

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Poster: P2-130

Author: Niccolò Ricardi

Title: Polarisation and response in Frozen Density Embedding

Synopsis: Within the framework of Frozen Density Embedding Theory, we selected embedding protocols which differ in the way the environment's density is generated, resulting in different ways to model polarisation and environment response, and used them to analyse systems with varying extent of polarisation and environment response. Through this, we aim to understand the sources of error in different types of interactions, and guide the selection of an appropriate protocol for the system at hand.

Room: Arbeidskontoret-1+2

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Poster: P2-131

Author: Fabian Glaab

Title: Charge transfer in mixed valence states: relaxation dynamics and transient absorption spectroscopy

Synopsis: Quantum dynamical model calculations are performed on the photo-induced electron transfer in a mixed valence system in different solvents. The transient absorption traces are in agreement with the experiment. The analysis of the dynamics documents that the ultrafast electron-transfer processes take place on a sub-picosecond time scale and afterwards relaxation occurs within several picoseconds.

Room: Arbeidskontoret-1+2

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Poster: P2-132

Author: Jan-Erik Oest

Title: Water on rutile (110): A 5 dimensional wave packet dynamics study of photocatalysis

Synopsis: Our goal is to make high dimensional exact wave packet dynamics simulations of large systems feasible by finding the right parameters to get high accuracy expectation values and at the same time keep hardware demands at a minimum. We want to use these simulations to study photocatalytic reactions of small molecules on semiconductor surfaces and understand their mechanisms on a quantum level.

Room: Arbeidskontoret-1+2

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Poster: P2-133

Author: Samuele Giannini

Title: Quantum Localization and Delocalization of Charge Carriers in Organic semiconducting Crystals

Synopsis: We apply atomistic non-adiabatic molecular dynamics to study charge transport and wavefunction localization and delocalization in application relevant organic semiconductors. Good agreement with experimentally measured mobilities is obtained over three orders of magnitude successfully bridging the regime where hopping and band models are invalid. New insights into the charge transport mechanism will be discussed.

Room: Arbeidskontoret-1+2

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Poster: P2-134

Author: Maud Chan-Yao-Chong

Title: Structural characterization of the intrinsically disordered N-WASP domain V and its recognition by actin

Synopsis: The Neural Wiskott-Aldrich Syndrome Protein is a pivotal protein in the regulation of the actin cytoskeleton. The characterization of the N-WASP fully disordered domain V is particularly challenging. We obtained realistic conformational ensembles from molecular dynamics techniques validated by NMR/SAXS data. We used representative structures of the most populated clusters of a conformational ensemble to model the interaction between N-WASP domain V and actin.

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Poster: P2-135

Author: Zhao-Ying Chern

Title: Mechanistic study of sulfur-poisoning and removal reactions of barium zirconate-based anodes: An ab initio atomistic calculation

Synopsis: In the present study, we investigated the mechanism of sulfur-poisoning and removal reactions on the Y and Yb doped barium zirconate (BaZrO3), the perovskite ceramic widely employed for solid oxide fuel cell (SOFC) application, by ab initio atomistic calculation.

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Poster: P2-136

Author: Hsin-Yi Liao

Title: How Argon Atom Affects the Vibrational Structure of Protonated Nitrogen Dimers?

Synopsis: The effect of the Ar atom in the vibrational spectra of protonated nitrogen dimers are investigated. Comparison of the calculated spectrum for the bare N4H+ ion and Ar-tagged N4H+ ion reveal that the reduction of the symmetry group results to a richer vibrational structure. These findings demonstrate the active role of the messenger atom in relaxing some of the selection rules for the bare ion– resulting to an augmentation of the bands in the action spectrum.

Room: Arbeidskontoret-1+2

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Poster: P2-137

Author: Chi-You Liu

Title: Termination Effects of Pt/v-Tin+1CnT2 MXene Surfaces for Oxygen Reduction Reaction Catalysis

Synopsis: We focus on the termination effects of MXene, which may be an important factor to enhance the performance of ORR. In conclusion, the F-terminated surfaces are predicted to show a better performance for ORR but with a lower stability than the O-terminated counterparts, and the underlying mechanisms are investigated in detail. We provides a better understanding of the electronic effect induced by the terminators and may inspire realizations of practical MXene systems for ORR catalysis.

Room: Arbeidskontoret-1+2

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Poster: P2-138

Author: Stefan Goedecker

Title: Finding reaction pathways with optimal atomic index mappings

Synopsis: A method is presented that allow us to find fully automaticaly reaction pathways where it is not known which atom in the educt is mapped onto which atom in the product.

Room: Arbeidskontoret-1+2

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Poster: P2-139

Author: Xin Gui

Title: Application of GW-BSE theory to transition-metal complexes

Synopsis: The Bethe-Salpeter equation (BSE) approach applied within the GW approximation has in recent years attracted considerable interest in calculating molecular excitation energies. It has the same scaling with respect to system size as time-dependent density functional theory (TDDFT), while it can overcome the TDDFT limitations associated with charge-transfer (CT) excitations. Here we present a few examples of application of GW-BSE to transition-metal complexes.

Room: Arbeidskontoret-1+2

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