Session D37: Focus Session: Fundamental Developments in Density Functional Theory III

2:30 PM–5:30 PM, Monday, March 16, 2009
- 409

Sponsoring Unit: DCP
Chair: Alberto Castro, Free University of Berlin

Abstract ID: BAPS.2009.MAR.D37.2

Abstract: D37.00002 : Van der Waals Interactions in Density-Functional Theory.

3:06 PM–3:42 PM

Preview Abstract

Author:

  Axel Becke
    (Dalhousie University)

The application of conventional GGA, and meta-GGA, density functionals to van der Waals complexes is fraught with difficulties. Conventional functionals do not contain the physics of the dispersion interaction. To make matters worse, the exchange part alone can yield anything from severe over-binding to severe over-repulsion depending on the choice of functional. We rectify these problems by - adding a dispersion term with nonempirical C6, C8, and C10 dispersion coefficients (the Becke-Johnson dispersion model), and - selecting a GGA exchange functional (PW86, also nonempirical) that gives excellent agreement with exact Hartree-Fock repulsion curves. The result is a simple GGA+dispersion theory giving excellent noble-gas pair interaction energies for He through Kr with only two adjustable parameters in the dispersion cutoff.

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2009.MAR.D37.2