PtN in zinc-blende structure: An unstable metallic transition-metal nitride compound

Abstract

Using the first principle calculations based on density function theory with the generalized gradient approximation and local density approximation，we studied electronic structure and mechanical stability of the recently synthesized nitrid e compound PtN with cubic structure. The results show that the PtN with zinc-ble nde structure is unstable. We further find that the rock-salt structure has a b igger cohesive energy than the zinc-blende structure, it is possible that a pha se transition from zinc-blende to rock-salt occurs under certain pressure.