Analysis of thermoelastic properties of alkali halide crystals at high temperatures

We have computed thermal expansivity, volume expansion, interatomic distances and isothermal bulk modulus of sixteen alkali halides with rock-salt structure at high temperatures up to their melting points. We have used the Anderson model based on the Anderson-Grüneisen parameter which involves volume thermal expansion coefficient, isothermal bulk modulus, and its temperature derivative. The Anderson model is based on the assumption that the Anderson-Grüneisen parameter remains constant with the change in temperature. The results obtained using this model have been found to present close agreement with the available experimental data. We have also considered the model due to Liu which takes into account the temperature dependence of the Anderson-Grüneisen parameter via its volume dependence. The results obtained from the two models have been found to compare well with each other and also with the available experimental data. The results could be useful for experimental studies.