Monte-Carlo Simulation of Molten CsCl Using a ‘Deformation Dipole’ Polarisable Ion Potential

Abstract

We have simulated the structure of molten CsCl at 943 K using a form of interionic potential, based on the deformation dipole model of Hardy and Karo, where ions have both point charges and dipoles. The magnitude of the dipole on an ion is determined by two factors, one being the local electric field and the other the repulsive potential due to overlap with neighbouring ions. Parameters are determined directly from the crystal lattice constant, compressibility and dielectric constants. Good agreement with experimental results is obtained. The potential is compared to the shell model of ionic polarisability which does not produce good agreement with experiment.

Key Words:

• Monte Carlo
• polarisable ion
• deformation dipole
• shell model
• molten salt