Study of hydrostatic pressure effect on structural, mechanical, electronic and optical properties of KMgF3, K0.5Na0.5MgF3 and NaMgF3 cubic fluoro-perovskites via ab initio calculations

The importance of fluoro-perovskites, especially KMgF3 and NaMgF3, for the industrial technology is indisputable. The flagrant lack of adequate information on K0.5Na0.5MgF3 motivated us to undertake a comprehensive study of their behavior under the effect of hydrostatic pressure. The scope of the study includes theoretical prediction in order to analyze and provide more information on the structural, mechanical, electronic and optical properties under the effect of pressure and their mechanical stability using all-electron self-consistent full-potential linearized augmented plane waves plus local orbital (FP-(L)APW+lo) method. Structural and elastic properties such as the lattice parameter, bulk modulus, its pressure derivative and the cohesive energy of KMgF3, K0.5Na0.5MgF3 and NaMgF3 as well as the effect of pressure on the values of lattice parameter, elastic constants and their related parameters have been predicted using GGA-PBE and GGA-PBEsol. These functionals have shown great success in the predic...