Structural stabilities and band structure characteristics of platinum nitride (PtN) via first-principles calculations

The structural phase transformations of the PtN compound with a 1:1 stoichiometric ratio of Pt:N were investigated using the framework of density functional theory (DFT). The full potential linearized augmented plane wave (FP-LAPW) method within the generalized gradient (PBE-GGA) and the Engel-Vosko generalized gradient (EV-GGA) approximations were used. A comparative study of the experimental and theoretical results is provided on the structural properties of zinc-blende (ZB), rock-salt (RS), cesium chloride (CsCl), wurtzite (WZ), nickel arsenide (NiAs), lead monoxide (PbO), and tungsten carbide (WC) phases. The calculated band structure using the modified version of the Becke and Johnson (mBJ) exchange potential reveals the metallic character of the PtN compound. The present study also shows that the PtN compound crystallizes in the WZ phase under ambient conditions. The theoretical transition pressures from WZ to RS, NiAs, PbO, and CsCl transformations are found to be 9.441 GPa, 7.705 GPa, 18.345 GPa and 31.9 GPa, respectively, using the PBE-GGA method.