Interionic potentials for alkali halides

Abstract

The authors have developed new potentials describing the short-range interactions between ions in the alkali halides. They have used the measured elastic constants to fix the near-neighbour overlap repulsion and study the second-neighbour potentials. The description of the next-neighbour interactions requires the inclusion of large van der Waals attractions, in general accord with latest estimates of these forces. They have used theoretical estimates of the repulsive part of the second-neighbour interaction and added a variable attractive part to fit the crystal data. The authors have first used a conventional Buckingham potential, but a more flexible form is required to provide a completely coherent picture of these interactions in the whole series of alkali halides.