Vibrational properties of bcc U and Mo at different temperatures

Abstract

An accurate description of the vibrational density of states is required for calculation of thermodynamic properties of crystal lattices as well as defect migration rates in the Vineyard theory framework. In this work we use EAM and MEAM interatomic potentials and apply the zero temperature lattice dynamics calculations and the velocity autocorrelation function calculations at finite temperatures to study vibrational density of states in bcc molybdenum and bcc uranium lattices. The latter case is especially interesting since γ-U is thermodynamically not favorable at low temperatures and is not observed in experiments.