A density-functional model of the dispersion interaction

Axel D. Beckea) and Erin R. Johnson

• Department of Chemistry, Queen’s University, Kingston, Ontario K7L 3N6, Canada
• a)Electronic mail: becke@chem.queensu.ca

ABSTRACT

We have recently introduced [J. Chem. Phys. 122, 154104 (2005)] a simple parameter-free model of the dispersion interaction based on the instantaneous in space, dipole moment of the exchange hole. The model generates remarkably accurate interatomic and intermolecular C6$C_6$ dispersion coefficients, and geometries and binding energies of intermolecular complexes. The modelinvolves, in its original form, occupied Hartree-Fock or Kohn-Sham orbitals. Here we present a density-functional reformulation depending only on total density, the gradient and Laplacian of the density, and the kinetic-energy density. This density-functional model performs as well as the explicitly orbital-dependent model, yet offers obvious computational advantages.

To download the article click on the link below:

http://aip.scitation.org/doi/abs/10.1063/1.2065267?mi=40xqag&af=R&ConceptID=774&ContribAuthorStored=Becke%2C+Axel+D&target=topic