Prediction of physical properties of XO (X = Am, Cd, Mg, Zr) compounds using density functional theory

Abstract

The electronic, mechanical and thermodynamic properties of XO ( \( {\rm X}= {\rm Am}\) , Cd, Mg, and Zr) compounds are studied by performing density functional theory (DFT) calculations. We have calculated the elastic constant, various moduli, phonon dispersion relation, and density of phonon state, heat capacity, density of state, electronic band structure, Debye temperature, free energy and enthalpy of the compounds. For this goal, we have performed our calculations within local density approximation (LDA) functional with ultra-soft pseudopotentials (USP) and generalized gradient approximation (GGA). According to the obtained results, it is found that i) CdO and ZrO compounds are ductile and MgO is a brittle material; ii) ZrO is less stable against shear forces than MgO and CdO; iii) at high temperatures, the heat capacity and Debye temperature approach a constant value for all compounds; iv) at temperatures higher than 60K, the averaged sound velocity in CdO is higher than MgO and ZrO; v) the ZrO and CdO are treated properly using GGA.