Unraveling Thermal and Dynamical Properties of the Cubic $\mathrm{BaVO}_3$ Perovskite from First-Principles Calculation

Abstract

Using a toolkit of theoretical techniques comprising ab initio density functional theory calculations and quasiharmonic approximation, we investigate temperature dependence of dynamical properties of $\mathrm{BaVO}_3$ perovskite. This interest is triggered by the fact that, recently, it was possible to synthesize a $\mathrm{BaVO}_3$ perovskite, in a cubic phase, at high pressure and temperature. First-principle calculations are achieved thanks to recent development in numerical facilities, especially phonon dispersion curves which are then fully obtained. Elastic constants of the compound are dependent on temperature due to the inevitable anharmonic effects in solids. We show that at low temperature, the full account of the thermal effects incorporating the phonon densities and Sommerfeld model is more appropriate to calculate the thermal properties of a metal.