Weil Matthias
Institute for Chemical Technologies and Analytics, Division of Structural Chemistry, Vienna University of Technology, Getreidemarkt 9/164-SC, A-1060 Vienna, Austria.
Acta Crystallogr Sect E Struct Rep Online. 2008 Dec 20;65(Pt 1):i2. doi: 10.1107/S1600536808043171.
In contrast to the previous refinement from photographic data [Ferrari et al. (1955 ▶). Gazz. Chim. Ital.84, 169-174], the present redetermination of the title compound, caesium hexa-aqua-magnesium arsenate(V), revealed the Cs atom to be on Wyckoff position 4d instead of Wyckoff position 4b of space group F3m. The structure can be derived from the halite structure. The centres of the complex [Mg(OH(2))(6)] octa-hedra and the AsO(4) tetra-hedra (both with 3m symmetry) are on the respective Na and Cl positions. The building units are connected to each other by O-H⋯O hydrogen bonds. The Cs(+) cations (3m symmetry) are located in the voids of this arrangement and exhibit a regular cubocta-hedral 12-coordination to the O atoms of the water mol-ecules. The O atom bonded to As has 2mm site symmetry (Wyckoff position 24f) and the water-mol-ecule O atom has m site symmetry (Wyckoff position 48h).
与之前根据摄影数据进行的精修结果[法拉利等人（1955年▶）。《意大利化学学报》84卷，169 - 174页]不同，此次对标题化合物六水合砷酸镁铯（V）的重新测定表明，Cs原子位于空间群F3m的Wyckoff位置4d，而非4b。该结构可由石盐结构推导而来。[Mg(OH₂)₆]八面体和AsO₄四面体（均具有3m对称性）的中心分别位于相应的Na和Cl位置。这些结构单元通过O - H⋯O氢键相互连接。Cs⁺阳离子（3m对称性）位于这种排列的空隙中，并与水分子的O原子呈现规则的立方八面体12配位。与As键合的O原子具有2mm位点对称性（Wyckoff位置24f），水分子的O原子具有m位点对称性（Wyckoff位置48h）。
