Abstract

Polycrystals of the BiFe₂(PO₄)₃ compound and Bi_1 – xSb_хCr₂(PO₄)₃ solid solution, which form a family isostructural to α-CaMg₂(SO₄)₃ (sp. gr. P6₃/m), have been synthesized from an aqueous solution by the salt co-precipitation method. The samples are characterized by X-ray diffraction, IR spectroscopy, differential thermal analysis, and thermogravimetry, microprobe analysis. The BiFe₂(PO₄)₃ single crystals have been grown by the flux method. The structure consists of polyhedra of three types: PO₄ tetrahedra, two face-sharing FeO₆ octahedra, and BiO₆ octahedra. Isolated PO₄ tetrahedra, which share oxygen vertices with doubled FeO₆ octahedra, form a three-dimensional [Fe₂(PO₄)₃]_3∞ framework, whose voids are occupied by bismuth atoms. Structures of the BiFe₂(PO₄)₃ and NASICON types are compared.

中文翻译：

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金属阳离子氧化态III形成的两种磷酸盐代表的合成与结构，α-CaMg2（SO 4）3类似物

摘要

所述BIFE的多晶体₂（PO ₄）₃化合物和Bi _{1 -  X}锑_х的Cr ₂（PO ₄）₃固体溶液，其形成家庭等结构，以α-为CaMg ₂（SO ₄）₃（SP克。。P 6 ₃ / m），是通过盐共沉淀法从水溶液中合成的。样品通过X射线衍射，IR光谱，差热分析以及热重分析和微探针分析进行表征。BiFe ₂（PO ₄）₃通过熔剂法已经生长了单晶。该结构由三种类型的多面体组成：PO ₄四面体，两个面共享FeO ₆八面体和BiO ₆八面体。孤立的PO ₄四面体与氧顶点加倍FeO ₆八面体共享氧顶点，形成三维[Fe ₂（PO ₄）₃ ] _3∞骨架，其空隙被铋原子占据。比较了BiFe ₂（PO ₄）₃和NASICON类型的结构。