钛酸锶钡的铁电相变与晶胞体积的关联

考察了Ba_μSr_1-μTiO₃(BST)的T_C对晶格 参数γ的依赖关系.并对BST的依赖关系与BaTiO₃和SrTiO₃的相应依 赖关系进行了比较.得到了一个观点：BST的T_C的变化可归因于晶胞体积效应.还 从体积效应的观点对BST相变的弥散性和级进行了讨论.BST的晶胞体积效应可归因于BST中Ba 和Sr的离子化现象. 关键词： 铁电性 钛酸锶钡 晶胞体积效应

A CORRELATION BETWEEN THE FERROELECTRIC PHASE TRANSITION AND THE CELL VOLUME IN BARIUM STRONTIUM TITANATE

The T_C of Ba_μSr_1-μTiO₃(BST) as a f unction of the composition and the lattice parameter γ is examined. It is compa red with the lattice parameter dependence of T_C of BaTiO₃ and SrTiO₃ respectively. It is argued that the variation of T_{C in BST can be attributed to the change of cell volume. The order and the di ffuseness of the phase transition are also discussed from the volume effect view point. The fact that the Ba and Sr are ionized leads to the volume effect of BST .}