Crystallochemical Features of the Simplest and Mixed-Layered Bismuth Oxides

Resumo

The family of bismuth ferroelectrics with a layered structure has generated considerable interest for researchers from both theoretical and practical perspectives for over half a century. The theoretical interest is due to the original structure of the compounds which have a high temperature of blurred ferroelectric transition, and the practical interest is due to the possibility of obtaining multifunctional materials. The crystallochemical analysis of the least studied species of the family, namely, the simplest compositions of the Bi₂O₃–second oxide type and complex intergrowth structures, compounds with the so-called mixed-layered structure of the grids, is presented. Crystallochemical formulas are proposed to describe the compositions of the above-mentioned types of structures, which should promote more purposeful synthesis of new compounds of the family.