Zhang Ai-Yun, Zheng Juan, Wang Qiu-Fen
Department of Physics and Chemistry, Henan Polytechnic University, Jiaozuo 454000, People's Republic of China.
Acta Crystallogr C. 2010 Mar;66(Pt 3):i22-4. doi: 10.1107/S0108270110001393. Epub 2010 Feb 3.
The novel hydrothermally synthesized title compound, pentabarium tetrachloride octahydrate octakis(oxovanadium phosphate), Ba(5)Cl(4)(H(2)O)(8)(VPO(5))(8), crystallizes in the orthorhombic space group Cmca with a unit cell containing four formula units. Two Ba(2+) cations, two Cl(-) anions and the O atoms of four water molecules are situated on the (100) mirror plane, while the third independent Ba(2+) cation is on the intersection of the (100) plane and the twofold axis parallel to a. Two phosphate P atoms are on twofold axes, while the remaining independent P atom and both V atoms are in general positions. The structure is characterized by two kinds of layers, namely anionic oxovanadium phosphate (VPO(5)), composed of corner-sharing VO(5) square pyramids and PO(4) tetrahedra, and cationic barium chloride hydrate clusters, Ba(5)Cl(4)(H(2)O)(8), composed of three Ba(2+) cations linked by bridging chloride anions. The layers are connected by Ba-O bonds to generate a three-dimensional structure.
新型水热合成的标题化合物八水合四氯化五钡八聚（氧钒磷酸），Ba₅Cl₄(H₂O)₈(VPO₅)₈，结晶于正交晶系空间群Cmca中，晶胞包含四个化学式单元。两个Ba²⁺阳离子、两个Cl⁻阴离子以及四个水分子的O原子位于（100）镜面，而第三个独立的Ba²⁺阳离子位于（100）平面与平行于a的二重轴的交点处。两个磷酸P原子位于二重轴上，而其余独立的P原子和两个V原子处于一般位置。该结构的特征在于两种层，即由共角VO₅四方锥和PO₄四面体组成的阴离子氧钒磷酸（VPO₅）层，以及由通过桥连氯离子阴离子连接的三个Ba²⁺阳离子组成的阳离子氯化钡水合物簇Ba₅Cl₄(H₂O)₈层。这些层通过Ba - O键连接以生成三维结构。
