Structural, elastic and electronic properties of the hexagonal anti-perovskites SbNBa3 and BiNBa3

Ab initio pseudo-potential plane-wave calculations are performed for the first time to explore the structural, elastic and electronic properties of the hexagonal anti-perovskite compounds SbNBa3 and BiNBa3 under pressure effect up to 20 GPa. The equilibrium structural parameters, energy band structure, density of states, charge density distribution and elastic parameters for single and polycrystalline SbNBa3 and BiNBa3 have been investigated using the recently developed Wu-Cohen generalized-gradient approximation (GGA-WC). From the elastic parameters we have derived some related properties such as the sound velocities and the Debye temperature for isotropic polycrystalline SbNBa3 and BiNBa3 aggregates.