The reactivity of FeMoO₄ in CsCl fluxes has been investigated by thermal analysis and chemical reactions in evacuated silica ampules. The products have been characterized by ex situ X-ray diffraction methods. Metathesis reactions involving CsCl lead to the formation of Cs₂Fe₂(MoO₄)₃ and the salt adduct Cs₂FeCl₄·CsCl. A side reaction has been observed, which is associated with a decomposition of [MoO₄]^2– in CsCl fluxes yielding Cs₂Mo₂O₇·CsCl, which contains the rare pyromolybdate anion, [Mo₂O₇]^2–, located in the center of a _∞²[CsCl] hetero-honeycomb arrangement. This salt-inclusion type of compound has been studied further in terms of its formation starting from Cs₂MoO₄, MoO₃, and CsCl. The intermediate adduct phase, Cs₂MoO₄·MoO₃, contains uncharged _∞¹[MoO₂O_2/2] chains that react with CsCl at elevated temperatures to Cs₂Mo₂O₇·CsCl. Furthermore, the site preference for alkaline-metal cations (K⁺, Rb⁺, and Cs⁺) has been evaluated for a mixed substitution series. In accordance with the Pearson concept, the polarizability of the respect cation outweighs any size differences for the occupancy of the salt-intergrowth motif, the honeycomb part of the structure.

中文翻译：

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FeMoO4 在 CsCl 助熔剂中的反应性和包盐型化合物的形成

通过热分析和真空二氧化硅安瓿中的化学反应，研究了 FeMoO _{4在 CsCl 助熔剂中的反应性。}产品已通过非原位 X 射线衍射方法进行了表征。涉及 CsCl 的复分解反应导致形成 Cs ₂ Fe ₂ (MoO ₄ ) ₃和盐加合物 Cs ₂ FeCl ₄ ·CsCl。已观察到与 CsCl 助熔剂中的 [MoO ₄ ] ^2-分解产生的副反应有关，产生 Cs ₂ Mo ₂ O ₇ ·CsCl，其中包含稀有的焦钼酸盐阴离子 [Mo ₂ O₇ ] ^2–，位于_∞ ² [CsCl] 异质蜂窝排列的中心。_{从Cs 2} MoO ₄、MoO ₃和CsCl开始，这种包盐型化合物已被进一步研究。中间加合物相Cs ₂ MoO ₄ ·MoO ₃包含不带电的_∞ ¹ [MoO ₂ O _2/2 ] 链，在升高的温度下与CsCl 反应生成Cs ₂ Mo ₂ O ₇ ·CsCl。此外，碱金属阳离子（K ⁺，Rb⁺和 Cs ⁺ ) 已针对混合替换系列进行了评估。根据 Pearson 的概念，相对于盐共生基序（结构的蜂窝部分）的占有率，相关阳离子的极化率超过了任何尺寸差异。