A molecular dynamics study on BaUO3

Abstract

The molecular dynamics (MD) calculation was performed for BaUO3 in the temperature range from 300 K to 2000 K to evaluate the physicochemical properties viz., the lattice parameter, thermal expansion coefficient (α), compressibility (β), heat capacity, and thermal conductivity. The parameters of the interatomic potential were determined by fitting to the experimental values of the lattice parameter for BaUO3. The heat capacity at constant volume (CV) was evaluated from the variation of the internal energy of the system by fixed volume MD calculation. The lattice dilational contribution to the heat capacity (Cd) was calculated from α and β. The MD calculation results of (Cv + Cd) almost agreed with the experimental data. The thermal conductivity (γ) was calculated by using a Green-Kubo relation. The temperature dependence of calculated γ followed a 1/T law, which indicates that the lattice contribution to the thermal conductivity (γlat) could be evaluated by the MD calculation. These results showed that MD techniques can be usefully applied to evaluate the physicochemical properties of BaUO3.