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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