Thermo-physical properties of LiH at high pressures by ab initio calculations

Abstract

First principles calculations have been carried out to analyze structural stability and to determine the equation of state and elastic constants of LiH as a function of pressure. The comparison of total energies of B1 and B2 structures determined as a function of compression suggests the B1 → B2 transition at ˜327 GPa. Various physical quantities including zero pressure equilibrium volume, bulk modulus, pressure derivative of bulk modulus, Debye temperature, bulk sound speed, Hugoniot parameter 's' and Gruneisen parameter have been derived. All these physical quantities compare well with the available experimental data. The single crystal elastic constants have been evaluated up to the B1→ B2 transition pressure.