A simple approach to estimate the melting temperature of alkali halides

Abstract

In the present study, a thermodynamical formulation is developed to determine the melting temperature of alkali halides with increasing pressure. The model is used to estimate the melting temperature of alkali halides at different pressures qualitatively. The formulation is obtained using the Goyal and Gupta thermodynamic equation of state. The model calculations require the computed values of volume compression, bulk modulus and its first pressure derivative at varying pressures. It is noted from model calculations that melting temperature increases with pressure but not in linear manner. The present computed results for pressure dependent melting temperature are compared with the available simulated results. The approach is found to be valid as good agreement is observed between previous and present results. Graphs are plotted to depict the variation of melting temperature with isothermal pressure, thermal pressure and total pressure acting on the solid. The present study helps to understand the impact of pressure on melting temperature of alkali halides qualitatively. The model used can also extrapolate the results upto higher pressures.