Effect of three-body interactions on the electronic polarizabilities and photoelastic behaviour of ammonium halides

Abstract

The effect of three-body interactions (TBI) on the electronic polarizabilities and photoelastic behaviour of ammonium halides has been studied in the framework of a three-body force shell model. This model takes proper account of Cauchy violation and gives and excellent description of various crystal properties of ionic solids. The strain derivatives of electronic polarizabilities have been evaluated through the influence of crystal potential on the polarizabilities of ions. The photoelastic behaviour has been studied by determining the strain derivatives of electronic dielectric constant. The strain derivatives of electronic polarizabilities and dielectric constants for ammonium halides are reported for the first time.