Ab initio comparative study of the structural, elastic and electronic properties of SnAMn3(A=N,C) antiperovskite cubic compounds

The structural, elastic and electronic properties of intermetallic SnAMn3 compounds with the cubic antiperovskite structure have been investigated, by employing ab initio calculations. The elastic constants and their pressure dependence are calculated using the static finite strain technique. We derived the bulk, shear and Young’s moduli for ideal monocrystalline and for polycrystalline SnAMn3 aggregates which we have classified as ductile in nature. Band structures reveal that these compounds are strong conductors. The analysis of the site and momentum projected densities, valence charge density bond length, bond population and Milliken charges, shows that bonding is of covalent–ionic nature. We have found that the elastic constants C11C11, C12C12, C44C44 are in good correlation with the bonding properties.