Effective charges and lattice dynamics of zincblende structure crystals

Abstract

Abstract In an earlier paper (referred to as I) effective charges for a number of II‐VT and III‐V compounds have been obtained from a model of the chemical bond in these crystals. In the present paper, the dynamics of GaAs is studied using a variety of rigid‐ion models and some empirical rules are deduced regarding their accuracy. These rules are used to evaluate the zone‐boundary phonon frequencies for CdTe, InSb, and AlSb, which have nearly the same effective charges (in the scheme of the present work) as GaAs. Phonon frequencies have also been calculated for ZnS, which is more ionic than the crystals mentioned above. The two and three phonon spectra of AlSb are calculated in order to show a possible way of refining lattice dynamical calculations.