Synthesis of the novel perovskite-type oxyfluoride PbScO2F under high pressure and high temperature

We synthesized a novel perovskite-type oxyfluoride, PbScO2F, and investigated its crystal structure, thermal stability and dielectric properties. PbScO2F has a cubic perovskite-type structure with Pb ions displaced from the ideal A-site positions along the 〈110〉 direction. By thermal gravity and differential thermal analyses, we found that this compound is stable up to 963 K (690 °C) under ambient atmosphere. The dielectric permittivity of PbScO2F is approximately 80, at room temperature, which is almost the same as KTiO2F and smaller than that of PbFeO2F. Furthermore, an anomaly in the dielectric permittivity was observed in the vicinity of 100 K that seems to be related to the displacement of the Pb ions.