An Ab-initio Study of Structural and Electronic Properties of CaTe under High Pressure

Abstract

The crystal structure of the CaTe compound is studied up to 150 GPa under high hydrostatic pressure using the density functional theory (DFT) with the generalized gradient approximation (GGA). Pressure-volume relationships, structural transitions and electronic properties in CaTe compound are investigated using Siesta method. CaTe crystallizes in the NaCl-type (B1) structure (space group: $$Fm\bar {3}m$$ ) at ambient conditions, and transforms to CsCl-type (B2) structure (space group: $$Pm\bar {3}m$$ ) at high pressure. This transformation is based on a intermediate state with space group $$R\bar {3}m$$ . Moreover, the electronic band structure of the B1 and B2 structures of CaTe have been calculated. According to this calculation, obtained band gap values are in good agreement with the values reported in the literature.