Surface energy of a bounded electron gas: Analysis of the accuracy of the local-density approximation via<i>ab initio</i>self-consistent-field calculations

Abstract

We report an ab initio evaluation of the surface energy of a simple metal,\nperformed via a coupling-constant integration over the dynamical\ndensity-response function. The rapid rate of change of the electron density at\nthe surface is treated exactly. Long-range correlations are treated\nself-consistently in the random-phase approximation; short range correlations\nare included in time-dependent local density-functional theory. Our results\nprovide a numerical measure of the error introduced by the usual local-density\napproximation; this error is found to be small.\n