The crystal chemistry underlying ferroelectricity in Bi4Ti3O12, Bi3TiNbO9, and Bi2WO6
The crystal chemistry underlying ferroelectricity in Bi4Ti3O12, Bi3TiNbO9, and Bi2WO6
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DOI：
10.1016/0022-4596(91)90207-x
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发表时间：
1991-10
影响因子：
3.3
通讯作者：
R. Withers;J. G. Thompson;A. Rae
中科院分区：
文献类型：
--
作者：
R. Withers;J. G. Thompson;A. Rae
最近重新细化的晶体结构的Bi4Ti3O12，Bi3TiNbO9，和Bi2WO6基本上不同于早期报道的结构细化。这些材料中存在的主要结构扭曲的比较和铁电性的主要结构原因（在Bi4Ti3O12和Bi3TiNbO9）被示出为相对于TiO 6八面体的链，而不是钙钛矿B原子向八面体边缘移动的钙钛矿A位点中的Bi原子的a轴位移。通过使用调制结构的方法，这种位移和其他结构特征的驱动力可以简单地理解为满足键价要求的需要。
The recent rerefinements of the crystal structures of Bi4Ti3O12, Bi3TiNbO9, and Bi2WO6differ substantially from earlier reported structure refinements. A comparison of the major structural distortions present in each of these materials is presented and the main structural cause of ferroelectricity (in Bi4Ti3O12and Bi3TiNbO9) is shown to be thea-axis displacement of Bi atoms in the perovskite A sites with respect to the chains of TiO6octahedra and not the perovskite B atoms moving toward an octahedral edge. By using a modulated structure approach, the driving force for this displacement and other structural features can be simply understood in terms of the need to satisfy bond valence requirements.