Pressure dependence of elastic constants and related parameters for rocksalt MgO

Based on the full-potential linearized augmented plane wave (FP-LAPW) method within the density functional theory (DFT) in both the local density approximation (LDA) and the generalized gradient approximation (GGA) approaches, the elastic constants and some of their related parameters such as the bulk modulus, shear modulus, [1 0 0] Young's modulus, anisotropy factor, [1 0 0] Poisson's ratio, and internal strain parameter have been reported for MgO in the rocksalt structure. The overall agreement between our results and the available experimental and theoretical data is found to be reasonably good. The pressure dependence of all studied quantities has been investigated. The mechanical stability criteria for the material of interest for pressures up to 100 GPa are fulfilled.