Ab initio calculation of the thermodynamic properties of wurtzite ZnS: performance of the LDA and GGA

摘要

The thermod ynamic properties of wurtzite ZnS are investigated by performing ab initio density functional theory and density functional perturbation theory calculations. Using both the local density approximation and generalized gradient approximation for the exchange-correlation potential, we calculate the phonon dispersion curves and the phonon density of states. The calculated phonon frequencies at the center zone for the Raman-active and infrared-active modes (including LO-TO splitting) are assigned. The thermod ynamic functions are calculated by using the phonon density of states. The calculated values are in reasonable agreement with experimental data and other calculations.