Electrostatic effects on cluster simulation of ionic crystals and surfaces

Abstract

Local perturbations in ionic solids and surfaces are often studied with cluster models embedded in an electrostatic Madelung potential. This potential is usually represented by a finite set of point charges whose values are defined by using several different methods. Local properties seem to a large amount independent from the criteria adopted for defining the Madelung potential. In this study, the cluster electrostatic potential is defined unambiguously on the basis of a periodic calculation of the unperturbed crystal; this permits us to understand the reasons for the insensitivity of local properties to the quality of the Madelung potential © 2008 IOP Publishing Ltd.