Cuny Jerome, Gougeon Patrick, Gall Philippe
Sciences Chimiques de Rennes, UMR CNRS No. 6226, Université de Rennes I-INSA Rennes, Avenue du Général Leclerc, 35042 Rennes CEDEX, France.
Acta Crystallogr Sect E Struct Rep Online. 2009 Jun 13;65(Pt 7):i51. doi: 10.1107/S1600536809021928.
The crystal structure of dizinc trimolybdenum(IV) octa-oxide, Zn(2)Mo(3)O(8), has been redetermined from single-crystal X-ray data. The structure has been reported previously based on neutron powder diffraction data [Hibble et al. (1999 ▶). Acta Cryst. B55, 683-697] and single-crystal data [McCarroll et al. (1957 ▶). J. Am. Chem. Soc.79, 5410-5414; Ansell & Katz (1966 ▶) Acta Cryst.21, 482-485]. The results of the current redetermination show an improvement in the precision of the structural and geometric parameters with all atoms refined with anisotropic displacement parameters. The crystal structure consists of distorted hexa-gonal-close-packed oxygen layers with stacking sequence abac along [001] and is held together by alternating zinc and molybdenum layers. The Zn atoms occupy both tetra-hedral and octa-hedral inter-stices with a ratio of 1:1. The Mo atoms occupy octa-hedral sites and form strongly bonded triangular clusters involving three MoO(6) octa-hedra that are each shared along two edges, forming a Mo(3)O(13) unit. All atoms lie on special positions. The Zn atoms are in 2b Wyckoff positions with 3m. site symmetry, the Mo atoms are in 6c Wyckoff positions with . m. site symmetry and the O atoms are in 2a, 2b and 6c Wyckoff positions with 3m. and . m. site symmetries, respectively.
二锌三氧化钼（IV）（Zn₂Mo₃O₈）的晶体结构已通过单晶X射线数据重新测定。该结构先前已基于中子粉末衍射数据[希布尔等人（1999年▶）。《晶体学报》B55，683 - 697]和单晶数据[麦卡罗尔等人（1957年▶）。《美国化学会志》79，5410 - 5414；安塞尔和卡茨（1966年▶）《晶体学报》21，482 - 485]报道过。当前重新测定的结果表明，所有原子采用各向异性位移参数进行精修后，结构和几何参数的精度有所提高。晶体结构由扭曲的六方密堆积氧层组成，沿[001]方向的堆积序列为abac，并由交替的锌层和钼层维系在一起。锌原子占据四面体和八面体间隙，比例为1:1。钼原子占据八面体位置，并形成由三个MoO₆八面体组成的强键合三角形簇，每个八面体沿两条边共享，形成一个Mo₃O₁₃单元。所有原子都位于特殊位置。锌原子位于Wyckoff位置2b，具有3m点群对称性，钼原子位于Wyckoff位置6c，具有.m点群对称性，氧原子分别位于Wyckoff位置2a、2b和6c，具有3m和.m点群对称性。
