Anatole von Lilienfeld

Universität Basel, Switzerland

Abstract

Many of the most relevant observables of matter depend explicitly on atomistic and electronic details, rendering a first principles approach to computational materials design mandatory. Alas, even when using high-performance computers, brute force high-throughput screening of material candidates is beyond any capacity for all but the simplest systems and properties due to the combinatorial nature of compound space, i.e. all the possible combinations of compositional and structural degrees of freedom. Consequently, efficient exploration algorithms exploit implicit redundancies and correlations. I will discuss recently developed statistical learning and perturbation based approaches for interpolating quantum mechanical observables throughout compound space. Numerical results indicate promising performance in terms of efficiency, accuracy, scalability and transferability.

 

Fedor Goumans, Thomas Soini & Ole Carstensen

Software For Chemistry and Materials, Amsterdam.

Session 1: Molecules

by Fedor Goumans

  • Short introduction Amsterdam Modeling Suite & the Graphical Interface
  • Building & importing molecules and structures
  • Calculating spectroscopy properties: IR, UV/VIS, NMR
  • Conformers & Potential Energy Surfaces
  • Transition States

Session 2: Periodic Systems

by Thomas Soini & Ole Carstensen

  • Importing cif files, structure database, slicing surfaces, polymers and nanotubes
  • Electronic structure and properties of semiconductors
  • Mechanical properties of polymers
  • Molecule gun for high-impact processes and depositon
  • Battery discharge with Grand Canonical Monte Carlo

Professor Areski Nait Abdallah

Dept. Computer Science, University of Western Ontario
London, Canada

Abstract

According to Niels Bohr "If you can fathom quantum mechanics without getting dizzy, then you don’t understand any of it." Logic is the art of organizing the elements of the discourse so that the conclusions clearly and obviously follow from the premisses.
Logical studies of quantum mechanics took off with the landmark 1936 quantum logic paper of Birkhoff and von Neumann, contemporary with the discovery of the foundations of computer science by Curry, Church and Turing. The needs of quantum based computing, and the discovery of the tight relation between computing and logic highlighted by Curry-Howard correspondence motivate a novel constructive logic based approach to some fundamental experiments of quantum mechanics. More specifically, we address single photon self-interference experiments and the related wave-particle duality paradox.

 

Dr Lars Goerigk

Melbourne Centre for Theoretical and Computational Chemistry,
School of Chemistry, The University of Melbourne, VIC 3010, Australia

Video Recording

Video is available only for registered users.

Abstract

The importance of Density Functional Theory (DFT) to the chemical sciences is well known. However, despite today’s easy access to DFT software packages to everyone, there remains a large communication gap between DFT developers and users that has resulted in various misconceptions and the regular application of outdated procedures. One reason for this is the fact that there is not only one manifestation of DFT, but hundreds of approximations to the true, unknown functional. Naturally, not only users that are new to the field, but also experts can find this ever-growing `zoo’ of DFT approximations confusing.

This presentation provides an overview of the zoo of DFT methods and is suitable to both students that are new to the field and more experienced researchers. Rather than spending too much time on discussing the physical/mathematical foundation of DFT, I will focus on aspects that are relevant to computational applications with guidelines and recommendations as take-home messages that may assist in future research endeavours. After a short overview of the basic idea of DFT and Perdew’s famous Jacob’s Ladder classification of DFT approximations, I will cover how we can identify the best and most robust representatives of the zoo for applications to thermochemistry and kinetics. A special emphasis will be given to the importance of London-dispersion interactions. Towards the end, more specialised aspects will be discussed that may be of interest to more theoretically oriented viewers.

 

Trygve Helgaker

Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, Box 1033 Blindern, N-0315 Oslo, Norway

Video Recording

Abstract

In a strong magnetic field, chemistry changes: electronic states change their character, atoms and molecules change their shape, and their interactions with radiation are affected, often in a dramatic manner [1–8]. Perhaps most surprisingly, new bonding mechanisms occur, giving rise to molecules that do not exist on Earth but may exist elsewhere such as in the atmospheres of magnetic white dwarfs [4,5]. The exotic chemistry of atoms and molecules in strong magnetic fields provides a fresh perspective on the familiar chemistry on Earth; at the same time, it provides a stress test for quantum chemistry, whose methods have been developed for Earth-like conditions. Density-functional theory, for example, must be re-examined and adapted for the molecules in strong magnetic fields and such modifications have relevance also for the calculation of magnetic properties such as shielding constants and magnetizabilities [7].
In the talk, I give an overview of chemistry in strong magnetic fields and discuss the how the methods of quantum chemistry such as coupled-cluster theory [6] and density-functional theory [7] must be modified and adapted to study molecules and their electronic structure in magnetic fields.

helgaker image

 

Professor Gemma C. Solomon

Nano-Science Center and Department of Chemistry, University of Copenhagen

Video Recording

This recording is no longer available.

Abstract

Quantum interference is a fascinating effect that can manifest whenever the wave-like nature of matter dominates. In this talk, I provide a general introduction to quantum interference as it applies to coherent electron transport and more specifically how it manifests in molecules. Unlike the larger systems commonly studied in condensed matter physics, the small size of single molecules means that phase coherence can be easily maintained across the system and quantum interference effects observed at room temperature in solution. I will discuss the theoretical and experimental efforts to study interference effects in charge transport through molecules and finally outline our efforts to find quantum interference based single-molecule insulators. Remarkably, we can show in calculations that it is possible to make a molecular functional unit that is more insulating than a vacuum gap of the same dimensions. [1]

 

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