Synthesis and characterization of the first polyoxometalate possessing bicapped by antimony α-Keggin structure (C2N2H9)2[PMo5VMo7VISb2IIIO40]·2H2O

A novel polyoxometalate (C2N2H9)2[PMo5VMo7VISb2IIIO40]·2H2O (1), displays three-dimensional network consisting of one-dimensional sinusoidal chain [(Hen)2(H2O)2]2+ and two-dimensional layer formed by [PMo5VMo7VISb2IIIO40]2-. The structure unit [PMo5VMo7VISb2IIIO40]2- is the first example of bicapped by antimony α-Keggin structure.