High-temperature phase transitions, spectroscopic properties, and dimensionality reduction in rubidium thorium molybdate family.
High-temperature phase transitions, spectroscopic properties, and dimensionality reduction in rubidium thorium molybdate family.
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DOI：
10.1021/ic403003f
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发表时间：
2014-03
影响因子：
4.6
通讯作者：
B. Xiao;T. Gesing;P. Kegler;G. Modolo;D. Bosbach;H. Schlenz;E. Suleimanov;E. Alekseev
中科院分区：
文献类型：
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作者：
B. Xiao;T. Gesing;P. Kegler;G. Modolo;D. Bosbach;H. Schlenz;E. Suleimanov;E. Alekseev
通过高温固相反应合成了四种新型钼酸铷钍。使用单晶X射线衍射测定了Rb8Th(MoO4)6、Rb2Th(MoO4)3、Rb4Th(MoO4)4和Rb4Th5(MoO4)12的晶体结构。所有这些化合物均由 MoO4 四面体和 ThO8 方形反棱镜构成。研究的化合物采用从零维 (0D) 到三维 (3D) 的所有可能的结构维度：有限簇、链、片和框架。 Rb8Th(MoO4)6 在 0D 中结晶，含有 [Th(MoO4)6](8-) 簇。 Rb2Th(MoO4)3 的晶体结构基于具有[Th(MoO4)3](2-)配置单元的一维链。化合物 Rb4Th(MoO4)4 中存在二维片状结构，并且在 Rb4Th5(MoO4)12 中观察到具有由钍和钼酸盐多面体形成的通道的 3D 框架。报告了这些化合物的拉曼和红外光谱特性。采用热重-差示扫描量热分析和高温粉末衍射方法观察了 Rb2Th(MoO4)3 和 Rb4Th(MoO4)4 的温度依赖性相变效应。
Four new rubidium thorium molybdates have been synthesized by high-temperature solid-state reactions. The crystal structures of Rb8Th(MoO4)6, Rb2Th(MoO4)3, Rb4Th(MoO4)4, and Rb4Th5(MoO4)12 were determined using single-crystal X-ray diffraction. All these compounds construct from MoO4 tetrahedra and ThO8 square antiprisms. The studied compounds adopt the whole range of possible structure dimensionalities from zero-dimensional (0D) to three-dimensional (3D): finite clusters, chains, sheets, and frameworks. Rb8Th(MoO4)6 crystallizes in 0D containing clusters of [Th(MoO4)6](8-). The crystal structure of Rb2Th(MoO4)3 is based upon one-dimensional chains with configuration units of [Th(MoO4)3](2-). Two-dimensional sheets occur in compound Rb4Th(MoO4)4, and a 3D framework with channels formed by thorium and molybdate polyhedra has been observed in Rb4Th5(MoO4)12. The Raman and IR spectroscopic properties of these compounds are reported. Temperature-depended phase transition effects were observed in Rb2Th(MoO4)3 and Rb4Th(MoO4)4 using thermogravimetry-differential scanning calorimetry analysis and high-temperature powder diffraction methods.