The Van der Waals interaction of the hydrogen molecule - an exact local energy density functional

Abstract

We verify that the van der Waals interaction and hence all dispersion interactions for the hydrogen molecule given by: W"= -{A/R^6}-{B/R^8}-{C/R^10}- ..., in which R is the internuclear separation, are exactly soluble. The constants A=6.4990267..., B=124.3990835 ... and C=1135.2140398... (in Hartree units) first obtained approximately by Pauling and Beach (PB) [1] using a linear variational method, can be shown to be obtainable to any desired accuracy via our exact solution. In addition we shall show that a local energy density functional can be obtained, whose variational solution rederives the exact solution for this problem. This demonstrates explicitly that a static local density functional theory exists for this system. We conclude with remarks about generalising the method to other hydrogenic systems and also to helium.

11 pages, 13 figures and 28 references

References in corpus (1)

• Van der Waals Energies in Density Functional Theory

Cited by in corpus (2)

• 1-matrix functional for long-range interaction energy of two hydrogen atoms
• Closed-form expressions for correlated density matrices: application to dispersive interactions and example of (He)2