Pressure-induced phase transition and electronic properties of CdPX 3 (X = S and Se) by first-principles calculation

The two-dimensional (2D) transition metal thiophosphates family CdPS 3 and CdPSe 3 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 CdPX 3 are investigated up to 40 GPa using first-principles calculation. CdPS 3 undergoes reversible phase transitions at around 1.5 GPa and 25 GPa from C 2 /m structure to structure and then to P3 1m structure, while the reversible phase transitions of CdPSe 3 are found at approximately 13 GPa from R3 structure to P3 1m 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 CdPS 3 and CdPSe 3 , 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 CdPX 3 -type family under extreme conditions. Graphical abstract