First-principles investigations on electronic, elastic and thermodynamic properties of ZrC and ZrN under high pressure

An investigation on electronic structure, elastic and thermodynamic properties of ZrC and ZrN under high pressure has been conducted using first-principles calculations based on density functional theory (DFT) with the plane wave basis set as implemented in the CASTEP code. Our results demonstrate that the sequence of the pressure-induced structure transition of ZrC and ZrN is from NaCl-type (B1) to CsCl-type (B2) structure. The transition pressures are 295 and 205 GPa for ZrC and ZrN, respectively. The elastic constants, Debye temperature, and heat capacity each as a function of pressure and/or temperature of ZrN are presented.