Abstract: A new tungstosilicates polyoxometalate (C2H10N2)3(SiWⅤ2WⅥ10O40)·3H2O was prepared under hydrothermal conditions, and characterized by elemental analysis, IR and single crystal X-ray diffraction analysis. The title compound crystallized in a triclinic system, P-1 space group, a=1.3193(3) nm, b=1.3198(3) nm, c=1.3193(3) nm, α=76.05(3)°, β=76.13(3)°, γ=76.05(3)°, V=2.1231(7) nm3,Z=1,R1=0.0518,wR2=0.1355. The title compound is comprised of silica tungsten Keggin polyoxoanion, three ethylenediamine and water molecules. The hydrogen bonds among polyoxoanion, ethylenediamine and water molecules are responsible for the formation of its extended three dimensional structure. Magnetic measurement indicates that there exists antiferromagnetic interaction in the molecule.

Key words: tungstosilicates, supramolecular, Hydrothermal synthesis, magnetic properties