Cauchy discrepancy in the second order elastic constants, their pressure derivatives on the three body force shell model

Abstract

Expressions for the Cauchy discrepancies in the second order elastic constants and their pressure derivatives have been derived on the basis of the simplified three body force shell model of Verma and co-workers for NaCl and CsCl structures. It is shown that the three body force shell model qualitatively explains the Cauchy discrepancy in the measured pressure derivatives of the second order elastic constants for the NaCl structures.