Pressure Induced Unusual Multiferroicity in Perovskite PbCoO₃

We develop a global structure search approach to predict the ground state of magnetic materials based on the genetic algorithm. With this new approach, we predict that the unusual phase transitions can happen in the recently synthesized perovskite oxide PbCoO₃ [J. Am. Chem. Soc. 139, 4574 (2017)] under the different hydrostatic pressure. At low pressure, the PbCoO₃ phases are polar and weakly ferromagnetic, indicating that these phases are multiferroic. When the pressure is increased to 13 GPa, a polar-to-nonpolar transition takes place, which is associated with the charge order transition. The simultaneous A-site and B-site charge ordering pattern in the nonpolar phase is in agreement with the experimental result.