高圧力を利用したペロフスカイト型構造を持つ酸フッ化物の合成と結晶構造

抄録

In this article, our recent researches on the crystal structure of the perovskite-type oxyfluorides were reviewed. Parts of these compounds were synthesized using the cubic-multi-anvil type high-pressure apparatus. In cubic oxyfluorides, the displacement from ideal positions of an anion or a cation was observed and the ion species displaced depended on the tolerance factor. The oxyfluorides containing Pb and/or Mn ions had a tetragonal structure and PbMnO₂F containing both ions exhibit very high tetragonality (c/a=1.10). In addition, the solid solutions between a perovskite-type oxide and an oxyfluoride or a fluoride were synthesized using high-pressure apparatus. As the result, it was revealed that one of these solid solutions, (1−x)BaTiO₃-xKTiO₂F represented unique structures and interesting dielectric properties.