Explicitly non-local relation between kinetic and exchange energy densities in the Bardeen model of a planar metal surface

摘要

The infinite barrier model of a planar metal surface, going back to Bardeen, is shown to permit the kinetic energy density to be written explicitly in terms of the ground-state electron density and its first derivative. The exchange energy density is then written in what proves to be an explicitly non-local form in terms of the electron density. Finally, by integrating the first-order equation for the electron density in terms of the kinetic energy density, a precise relation is established in this metal surface model between exchange and kinetic energy densities. (author)