Transition phase and electronic structure of SrS under pressure from first-principles calculations

The transition phase and the electronic properties of SrS in the NaCl structure (B1) and the CsCl structure (B2) are investigated by ab initio plane-wave pseudopotential density functional theory method. The transition pressure obtained is in good agreement with the experimental data and other theoretical results. The pressure and temperature dependences of the band gaps of SrS in the B1 structure are presented. It is found that the effect of pressure on energy gaps is contrary to that of temperature. For SrS in the B2 structure, the pressure dependence of the band gaps is also plotted. The calculated metallization pressure is 63.3 GPa, well consistent with experimental and other theoretical data.