Hydrothermal Synthesis and Crystal Structure of a Novel Polyoxometalate K(C_4N_2H_(12))_4(C_4N_2H_(11))_2- [Mo_8~VMo_4~(VI)CdP_8O_(54)(OH)_8]F·6H_2O

The title compound 1 has been synthesized by the reaction of H2MoO4,CdCl2,H3PO4,KF,piperazine hexahydrate and water in aqueous solution under mild hydrothermal conditions. Single-crystal X-ray analysis reveals that the title compound crystallizes in the triclinic system,space group P1 with a = 14.049(3),b = 15.972(3),c = 20.043(4) ,α = 85.82(3),β = 81.28(3),γ = 67.15(3)°,V = 4095.9(14) 3,Mr = 3204.62,Z = 2,Dc = 2.598 g/cm3,μ = 2.360 mm-1,F(000) = 3124,the final R = 0.0314,wR = 0.0826 and S = 0.989 for 18592 observed reflections with I 2σ(I). The crystal packing is stabilized by N–H and O–H intra- and intermolecular hydrogen bonds to form an infinite 3D network.