Abstract

The evolution of the crystal structure of (1 – x)PbFe_2/3W_1/3O_{3 – x}PbTiO₃ solid solutions depending on the PbTiO₃ concentration (at x = 0.25, 0.3, and 0.35) near the morphotropic phase boundary has been investigated using X-ray diffraction at room temperature. It is established that all three compositions are mixtures of the cubic and tetragonal phases and that an increase in the PbTiO₃ concentration above 30 mol % increases the tetragonal-phase fraction. The crystal structure parameters and contents of both phases in these solid solutions are determined. It is shown that there exist static displacements of lead ions from the main crystallographic sites at room temperature.

中文翻译：

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（1 – x）PbFe 2/3 W 1/3 O 3 – x PbTiO 3固溶体（x = 0.25、0.3和0.35）的晶体结构的两相态在室温下

摘要

（1- x）PbFe _2/3 W _1/3 O _{3- x} PbTiO ₃固溶体的晶体结构根据向晶相界附近的PbTiO ₃浓度（在x = 0.25、0.3和0.35处）而发展。已在室温下使用X射线衍射进行了研究。可以确定所有三种成分都是立方相和四方相的混合物，并且PbTiO ₃的增加浓度高于30mol％会增加四方相的分数。确定这些固溶体中的晶体结构参数和两相的含量。结果表明，室温下铅离子会从主要的晶体学位置发生静态位移。