A tentative model for estimating the compressibility of rock-salt AgCl_{x}Br_{1-x} alloys

Abstract

Ab initio detailed calculations of the elastic properties of AgCl_{x}Br_{1-x} alloys recently appeared using density-functional perturbation theory and employing the virtual crystal approximation or by means of the full potential linearized augmented plane wave method. Here, we suggest a simple theoretical model that enables the estimation of the isothermal compressibility of these alloys in terms of the elastic data of end members alone. The calculated values are in satisfactory agreement with the experimental ones. The present model makes use of an early suggestion that interconnects the Gibbs energy for the formation and/or migration of defects in solids with bulk properties.