Fyzikální ústav Akademie věd ČR

Seminar Tuesday, 22/01/2013 15:00 - 16:00

Speakers: Jiří Klimeš (Faculty of Physics and Center for Computational Nanoscience, University of Vienna, Sensengasse 8/12, Wien, Austria)
Place: Na Slovance, main lecture hall
Presented in English
Organisers: Department of Condensed Matter Theory

Abstract: Van der Waals dispersion interactions are ubiquitous in nature and contribute to the binding of a range of systems such as DNA, graphite, or condensed phases of water. However, they are smaller in magnitude than covalent bonds and difficult to describe accurately with electronic structure methods, including the density functional theory (DFT). We will discuss the so-called van der Waals density functional (vdW-DF) [1], one of the schemes that has been proposed to cure the inability of standard DFT functionals to describe dispersion. Although a promising approach, we show that for many systems and properties it doesn't offer a satisfactory accuracy and present various ways how this can be improved [2,3]. We will discuss the benefits of using vdW-DF to study molecular adsorption and present some applications of it. This includes water adsorption on metals [4] and high pressure phases of ice [5] where dispersion plays a crucial role. Where possible, the method will be compared to higher level theory calculations [6] which sometimes show that there is still a scope for improvement and we will discuss some of the possible ways to improve the method further.

[1] Dion et al., Phys. Rev. Lett. 92, 246401 (2004),
[2] Klimes et al., J. Phys.: Cond. Matt. 22, 022201 (2010),
[3] Klimes et al., Phys. Rev. B 83, 195131 (2011),
[4] Carrasco et al., Phys. Rev. Lett. 106, 026101 (2011),
[5] Mittendorfer et al., Phys. Rev. B 84, 201401(R) (2011),
[6] Santra et al., Phys. Rev. Lett. 107, 185701 (2011)