Crystal structure, vibrational studies and optical properties of a new molybdo-tellurate Na6(TeMo6O24)(H2SO4)2•12H2O

Single crystals of a new molybdo-tellurate compound Na-6(TeMo6O24)center dot(H2SO4)(2)center dot 12H(2)O(I) were grown by the low-evaporation technique and characterized by X-ray diffraction, infrared absorption and UV-Vis absorption. The compound crystallizes in the monoclinic system and C2/m space group with a = 16.431(1) , b = 12.493(1) , c = 10.329(1) , beta = 109.55(1), V = 1998.1(2) (3), Z = 2, R = 0. 0.0395 and wR (F (2)) = 0.090 for 1890 unique observed reflections [I > 2 s(I)]. The crystal structures exhibit three-dimensional supramolecular assembly based on the extensive hydrogen bonding interactions between H2SO4 molecule, sodium cations, water molecules and Anderson polyoxoanions (TeMo6O24)(6-). The infrared spectrum fully confirms the X-ray crystal structure, and the UV spectrum of the title compound exhibits an absorption peak at 220 nm.