High-pressure phase transitions of Cu2O

In the present study, we extensively explored the crystal structures of Cu2O on increasing the pressure from 0 GPa to 24 GPa using the first-principles density functional calculations. A series of pressure-induced structure phase transitions of Cu2O are examined. The calculated results show that the phase transitions (Pn-3m phase -> R-3m phase -> P-3m1 phase) occur at 5 GPa and 12 GPa, respectively. The P-3m1 phase is found to be the metallic phase via band-gap closure under high pressure. (C) 2017 Elsevier Masson SAS. All rights reserved.