Pressure-induced phase transition and electronic properties of CdPX3 (X = S and Se) by first-principles calculation.

The two-dimensional (2D) transition metal thiophosphates family CdPS3 and CdPSe3 are supposed to explore pressure-relevant structural and electronic behaviors as support to build 2D spintronic devices. The pressure-induced phase transition and electronic properties of CdPX3 are investigated up to 40 GPa using first-principles calculation. CdPS3 undergoes reversible phase transitions at around 1.5 GPa and 25 GPa from C2/m structure to structure and then to P 3 ¯ 1 m structure, while the reversible phase transitions of CdPSe3 are found at approximately 13 GPa from R 3 ¯ structure to P 3 ¯ 1 m structure, reflected in the lattice constant mutation and cell volume collapse. The computed metallization transition is found at about 25 GPa and 13 GPa owing to energy band closure for CdPS3 and CdPSe3, respectively. As anisotropy increases with pressure, the enhanced metallic property is accompanied by the inter- and intra-layer sliding atom pairs induced by phase transition. The paper is conducive to considering the phase transition and metallization of CdPX3-type family under extreme conditions. [ABSTRACT FROM AUTHOR]