Defect energies in CsCl and its solid solutions with KCl, RbCl, and CsBr

Abstract

The formation energies of Schottky defects in the CsCl (Pm3m) and the NaCl (Fm3m) structures of CsCl are found to be 1·4 and 2·0 eV respectively. The ground-state interaction energies between Sr²⁺_Cs⁺ and the V^–_Cs⁺ in the Pm3m and Fm3m phases are ca. 0·45 and 0·35 eV respectively. The cation migration energies in CsCl are affected by the incorporation of K⁺, Rb⁺ or Br^–. The formation energy of Schottky defects in the solid solutions of CsCl with KCl or RbCl is low (1·4 eV) in the Pm3m phase, but attains a much higher value (2 eV) at compositions where the Fm3m structure gets stabilized.