Interatomic Interactions in Alkali Halides

Abstract

Abstract Using free ion orbitals two‐body and three‐body potentials between nearest and next‐nearest neighbours in several alkali halides have been calculated. The two‐body potentials have been calculated without any expansion in power‐series of overlap integral S . The three‐body potentials have been calculated approximately, only terms of the order S 2 being retained. The results show that the use of the free ion orbitals leads to somewhat too strong repulsion between the ions.