ANewSandwichTypeTransitionMetalSubstitutedPolyoxotungstateunderHydrothermalConditions:[NH3（CH2）4NH3]6[Co4（H2O）2(B-α-GeW9O34)2]}·7H2O

A new sandwich transition metal substituted polyoxotungstate, [NH3(CH2)4NH3]6 [Co4(H2O)2(B-α-GeW9O34)2]·7H2O 1, was hydrothermally synthesized and characterized by IR spectra and single-crystal X-ray diffraction. The single-crystal X-ray analysis reveals that the crystal crystallizes in monoclinic system, space group P21/c with a = 16.6073(6), b = 15.3333(5), c = 19.9869(7) , β = 103.41(1)o, Mr = 5481.38, V = 4950.8(3)3, Z = 2, Dc = 3.677 g/cm3, F(000) = 4900, μ(MoKα) = 22.165 mm–1, GOOF = 1.005, the final R = 0.0228 and wR = 0.0527. The crystal structure indicates that the [Co4(H2O)2(B-α-GeW9O34)2]12– polyoxoanion contains two trivacant Keggin [B-α-GeW9O34]10– fragments in a staggered fashion linked via a rhomb-like Co4O16 group in a centrosymmetric arrangement (C2h symmetry) leading to a sandwich-type structure.