Pseudopotential perturbation theory for the surface tension of liquid metals

Abstract

A theory for the surface tension of liquid metals is developed on the basis of the direct perturbation expansion to second order in the electron-ion pseudopotential. A simple and easily tractable expression for the surface tension is derived from an expression for the Helmholtz free energy which is generalised to a liquid metal with a planar surface. The variational method is used for determining both the electron and ion density profiles at the surface and the bulk radial distribution function is assumed for describing the correlation between ions in the transition zone.