First-principles calculation of elastic and thermodynamic properties of MgO and SrO under high pressure

The elastic constants of B1- and B2-type MgO and SrO are calculated by a first-principles method at ambient condition. For B1-type MgO and SrO, the dependence of the elastic constants, the bulk modulus B, the shear constants cS and the Cauchy relation on the applied pressure are presented. The calculated results agree quite well with the comparable experimental data and the values of other works. Moreover, the thermodynamic properties (Debye temperature, melting temperature) and sound velocity is investigated under high pressure for the first time.