STRUCTURAL ASPECTS OF PEROVSKITE-TYPE COMPOUNDS - SYMMETRY CHANGES IN SRCEO3 AND ITS SOLID-SOLUTIONS

Many ABO//3 perovskite-type compounds exhibit an orthorhombic symmetry with a congruent b and c congruent a ROOT 2 axis length. An important exception is the compound SrCeO//3 which exhibits a strongly distorted perovskite-type structure with 2 a congruent b. However, the doubling of the b axis in SrCeO//3 disappears both in the SrCeO//3 - SrZrO//3 and in the SrCeO//3 - BaZrO//3 solid solutions in all the compositions differing from the stoichiometric SrCeO//3.