Pressure variation of melting temperatures of alkali halides

Abstract

The melting temperatures of alkali halides (LiCl, LiF, NaBr, NaCl, NaF, NaI, KBr, KCl, KF, KI, RbBr, RbCl, RbI and CsI) have been evaluated over a wide range of pressures. The solid–liquid transition of alkali halides is of considerable significance due to their huge industrial applications. Our formalism requires a priori knowledge of the bulk modulus and the Grüneisen parameter at ambient conditions to compute [Formula: see text] at high pressures. The computed values are in very good agreement with the available experimental results. The formalism can satisfactorily be used to compute [Formula: see text] at high pressures where the experimental data are scanty. Most of the melting curves ([Formula: see text] versus [Formula: see text]) exhibit nonlinear variation with increasing pressure having curvatures downward and exhibit a maximum in some cases like NaCl, RbBr, RbCl and RbI. The values of [Formula: see text] and [Formula: see text] corresponding to the maxima of the curves are given.