High Pressure Study of IrN in Zinc-Blende Structure

Abstract

The structural phase transition, volume collapse and second order elastic constants of 5d-transition metal mononitride (IrN) have been investigated by using interaction potential model (IPM) which consists of Coulomb interaction, three-body interaction and short range overlap repulsive interactions. The present theoretical approach has predicted pressure-volume relationship curves which shows that IrN exhibits a zinc-blend (ZB) type structure at an ambient pressure and undergoes a structural phase transition from B3 to B1 phase at pressure 72 GPa. The equation of state shows volume collapse of 9.09 %. The phase transition pressure and associated volume collapses obtained from this model show a reasonable agreement with other theoretical results. The second order elastic constants are also investigated for ZB phase.

Keywords: High Pressure, Phase Transition, Transition Metal Compounds