Prediction study of the structural, elastic and electronic properties of ANSr3 (A = As, Sb and Bi)

Based on first-principles total energy calculations, we predict the elastic and electronic properties of the anti-perovskites AsNSr3, SbNSr3 and BiNSr3 compounds. The calculated lattice constants are in good agreement with the available results. The independent elastic constants (C11, C12 and C44) and their pressure dependence are calculated using the static finite strain technique. The isotropic elastic moduli, namely, bulk modulus (B), shear modulus (G), Young’s modulus (E), Poisson’s ratio (σ) and Lame’s constants (λ and μ) are calculated in framework of the Voigt–Reuss–Hill approximation for ideal polycrystalline ANSr3 aggregates. By analysing the ratio between the bulk and shear moduli, we conclude that ANSr3 compounds are brittle in nature. We estimated the Debye temperature of ANSr3 from the average sound velocity. The band structures show that all studied materials are semiconductors. The analysis of the site and momentum projected densities, charge transfer and charge densities show that bonding is of covalent–ionic nature. This is the first quantitative theoretical prediction of the elastic and electronic properties of AsNSr3, SbNSr3 and BiNSr3 compounds that requires experimental confirmation.