Ab initio calculations of the pressure-induced structural phase transitions for four II-VI compounds

We report on pseudopotential calculations of the structural properties and pressure-induced solid-solid phase transitions for four II-VI compounds: ZnSe, ZnTe, CdSe, and CdTe. For each of these compounds, we fix the zinc-blende structure as the ambient pressure phase and consider the rocksalt, cinnabar, and Cmcm structures as candidates for the high-pressure phases. We calculate the transition pressures and the changes in specific volume for each compound. The pressure dependences of the structural parameters of the cinnabar and the Cmcm phases are determined. The Cmcm structure appears to be a common high-pressure phase for the II-VI and III-V semiconductors.