Van der Waals interactions: Accuracy of pair potential approximations

Abstract

Van der Waals interactions between single atoms and solids are discussed for the regime of large separation. A commonly employed approximation is to evaluate this interaction as a sum of two-body interactions between the adatom and the constituent atoms of the solid. The resulting potentials are here compared with known results in various geometries. Analogous comparisons are made for diatomic molecules near either single atoms or semi-infinite surfaces and for triatomic molecules' interactions with single atoms.

Van der Waals interactions in density functional theory by combining the quantum harmonic oscillator-model with localized Wannier functions

“…5,11,21,22,28,29 Although the QHO model intrinsically describes manybody effects in the case of localized fluctuating dipoles, the present approach is not well suited for describing the response of delocalized electrons. In fact, for MLWFs characterized by large spread, the single QHO approximation is less appropriate, as the response of delocalized electrons is expected to be closer to that of a homogeneous electron gas.…”

Density-functional theory with screened van der Waals interactions applied to atomic and molecular adsorbates on close-packed and non-close-packed surfaces

“…Let us consider a homogeneous distribution of attractive forces within the substrate between atom a and each of the atoms s constituting substrate S given by the leading −C 6 R −6 term of the vdW interaction between two atoms. We can recover the inverse third power dependence on the distance by integrating the pairwise interaction over the volume of the substrate spanning the region S S [60,61]:…”