Crystal Structure of a New Cation-ordered Fluorite-related Phase: Bi2Te2WO10

Bi₂Te₂WO₁₀ crystallises in the monoclinic system (space group C2/c, Z = 4) with a = 12.4972(7) Å, b = 5.6414(3) Å, c = 12.2705(6) Å and β = 91.38(3)°. The structure has been solved by means of single crystal X-ray diffraction data analysis. The reliability factors are R1 = 0.030 and wR2 = 0.065 for 1258 structure factors and 70 parameters. The Bi₂Te₂WO₁₀ crystal structure can be described as a regular stacking along the Ox axis of polyhedral layers with the stereochemically active lone pairs E of the Bi^III and Te^IV atoms all located between these layers. The cohesion of the three-dimensional network is therefore only ensured between succesive layers by weak Bi? O(5) bonds.