High-pressure synthesis of LiNbO₃-type oxides with a polar structure

Abstract

Several LiNbO₃(LN)-type oxides with a polar structure have been synthesized by high-pressure and high-temperature heat treatment. Their crystal and electronic structures, and the physical properties such as polarity, dielectric permittivity, and magnetic susceptibility were investigated. The Goldschmidt's tolerance factor is not the only predominant factor with regards to the formation of LN-type phase and the chemical characters of constituent ions are also important. We discuss the stability, chemical bond and structure-properties relationship of LN-type oxides.