Vibrational properties of bcc U and Mo at different temperatures

31st International Conference on Equations of State for Matter

Fidanyan, K.S.^1,2 ; Stegailov, V.V.^1,2

Joint Institute for High Temperatures of the Russian Academy of Sciences, Izhorskaya 13, Moscow

125412, Russia^1

Moscow Institute of Physics and Technology, Institutskiy Pereulok 9, Dolgoprudny, Moscow Region

141700, Russia^2

关键词: Defect migrations;    Dynamics calculations;    Finite temperatures;    Interatomic potential;    Velocity autocorrelation functions;    Vibrational density of state;    Vibrational properties;    Zero temperatures;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/774/1/012031/pdf
DOI  :  10.1088/1742-6596/774/1/012031

来源: IOP

【 摘 要 】

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.