High-Pressure Phase Transitions and Thermodynamic Behaviors of Cadmium Sulfide

摘要: The pressure-induced phase transitions of cadmium sulfide semiconductor in both zinc-blende and wurtzite structures are investigated by ab initio plane-wave pseudopotential density functional theory with the local approximation. On basis fourth-order Birch-Murnaghan equation state, transition pressures P(t) determined enthalpy criterion. It is found that occur at pressure 2.57 GPa (zinc blende-rocksalt structure) 2.60 (wurtzite-rocksalt structure), respectively. equilibrium structural parameters, elastic constants, calculated compared experimental data available other theoretical results. According to linear-response approach, thermodynamic properties such as free energy, enthalpy, entropy, heat capacity also obtained successfully from phonon state.