High-pressure synthesis and characterization of a novel perovskite PbFe_1/2V_1/2O₃

Abstract

A novel perovskite, PbFe_1/2V_1/2O₃ was successfully synthesized under 7 GPa. PbFe_1/2V_1/2O₃ exhibits a highly distorted tetragonal perovskite structure (c/a = 1.18) with the disordered arrangement of Fe and V at room temperature. The XPS reveals that the oxidation states of each ion are Pb²⁺, Fe³⁺, and V⁵⁺, respectively. The large tetragonal distortion is related to not only the presence of Pb²⁺ ion but also V⁵⁺ with an electronic configuration of d ⁰. No structural phase transition up to 490 K above room temperature was observed by a high-temperature X-ray diffraction experiment. The temperature dependence of magnetic susceptibility exhibits non-Curie-Weiss behavior, which is attributed to the antiferromagnetic interaction between Fe³⁺-O^2--Fe³⁺ originated from the disordered arrangement of Fe³⁺ and V⁵⁺ ions.