Theoretical investigations of structural, elastic and thermodynamic properties for PtN2 under high pressure

Abstract We have investigated structural and elastic properties of PtN 2 under high pressures using norm-conserving pseudopotentials within the local density approximation (LDA) in the frame of density-functional theory. Calculated results of PtN 2 are in agreement with experimental and available theoretical values. The a / a 0 , V / V 0 , ductility/brittleness, elastic constants C ij , shear modulus C ′, bulk modulus B , shear modulus G , Young's modulus E , Poisson's ratio σ and anisotropy factor A as a function of applied pressure are presented. Through the quasi-harmonic Debye model, we also study thermodynamic properties of PtN 2 . The thermal expansion versus temperature and pressure, thermodynamic parameters X ( X =Debye temperature or specific heat) with varying pressure P , and heat capacity of PtN 2 at various pressures and temperatures are estimated.