Matthias Scheffler

October 4-8, 2010, Freiburg Germany

Prof. Matthias Scheffler

Fritz-Haber-Institut der Max-Planck-Gesellschaft
Faradayweg 4-6                  
D-14 195 Berlin-Dahlem / Germany

Phone: +49-30-8413 4711
Fax: +49-30-8413 4701
Email: Scheffler@fhi-berlin.mpg.de
http://www.fhi-berlin.mpg.de/th/

 

The Role of van der Waals Interactions in Physics, Chemistry, and Biology; Insights from DFT and Beyond

Abstract

Van der Waals (vdW) forces are crucial for the formation, stability, and function of molecules and materials. At present, ubiquitous vdW interactions are absent from essentially all local-, gradient-corrected, and hybrid functionals of density-functional theory (DFT). Recently we have developed an efficient method to obtain an accurate description of the long-range vdW interactions in terms of adding simple, pair wise C6[n]/R6  terms, where C6[n] is a functional, calculated from either DFT or Hartree-Fock: The so called DFT+vdW [1] and the MP2+ΔvdW [2] approach. In particular the latter has an accuracy close to that of the “gold standard” of quantum chemistry, namely CCSD(T).

We will briefly sketch the theory, also comparing it to other methodology, as for example Møller-Plesset perturbation theory, the vdW-DF (density functional) [3], and the highest level DFT approach, namely exact exchange plus correlation treated in the random phase approximation (EX+cRPA).

Examples to be discussed include bulk crystals, surfaces, organic/organic and organic/inorganic interfaces, and the unfolding dynamics of polyalanine helices.[4]

In all case it is found that vdW interactions play a noticeable if not crucial role, not just for quantitative values but also for the qualitative behavior.

[1] A. Tkatchenko and M. Scheffler, Phys. Rev. Lett. 102, 073005 (2009).

[2] A. Tkatchenko, et al., J. Chem. Phys. 131, 094106 (2009).

[3] M. Dion, et al., Phys. Rev. Lett. 92, 246401 (2004).

[4] A. Tkatchenko, M. Rossi, V. Blum, J. Ireta, M. Scheffler, to be published.

 

Brief Bio

Matthias Scheffler is director at the Fritz Haber Institute of the Max Planck Society and “Distinguished Visiting Professor for Computational Material Science and Engineering” at the UC Santa Barbara, where he spends about three months per year.

Scheffler’s research focuses on understanding fundamental aspects of physical and chemical properties of surfaces, interfaces, clusters, nanostructures, and bulk based on ab initio electronic-structure theory. Present activities include catalytic reactions at surfaces, atmospheric chemistry, magnetic semiconductors, high-k dielectrics, thermal conductivity, and biophysics. These are multi-scale modeling studies linking first principles electronic structure theory calculations, ab initio molecular dynamics, and methods from thermodynamics and statistical mechanics to enable understanding of meso- and macroscopic phenomena occurring under realistic (T, p) conditions.