Syntheses, Structure And Properties Of Novel Polyoxometalate Based On B-[SbW₉O₃₃]～(9-) Or Derivative Building Units

On the basis of molecular design and assembly, the polyoxometalate compounds based on B-[SbW9O33]9? or it′s derivative building units were successfully synthesized by the hydrothermal or routine methods by virtue of transition metal ions as bridges, and characterized by X-ray crystallography, spectroscopic, thermal, electrochemical and magnetic properties.(I) We obtained an organic-inorganic hybrid based on trivicant building unit [B-α-SbW9O33]9?: Na[{Cu(2,2′-bpy)(H2O)}2{Cu(2,2′-bpy)}2(B-α-SbW9O33)]?2H2O(1), which display a 1D chain in the help of Na+ ion.(II) Using hydrothermal synthetic technology, we have synthesized two organic-inorganic composite compounds, [Co(2,2′-bpy)3]2[Co(2,2′-bpy)2Cl][Co(2,2′-bpy)2]H2[SbW18O60]?4H2O (2) and [Cu(2,2′-bpy)3]2[Cu(2,2′-bpy)2Cl][Cu(2,2′-bpy)2]H6[SbWV4WVI14O60]?H2O (3). The results of the single crystal X-ray diffraction analyses show both compounds present a novel Dawson-like polyoxoanion.(III) Under routine conditions, using polyoxometalate precursor, we have synthesized three symmetrical sandwich-type compounds, Na8K[Na2K(H2O)2{Co(H2O)}3 (B-α-SbW9O33)2]?10H2O (4), K4Na2H3[Na2K(H2O)2{Cu(H2O)}3(B-α- SbW9O33)2]?15H2O (5) and NaH8[Na2Cu4Cl(B-α-SbW9O33)2]?21H2O (6). Compounds 4?6 display symmetrical sandwich-type polyanion framework based on [B-α-SbW9O33]9- building blocks, of which 6 displays a beautiful 2D layer-like structure.(IV) Under routine conditions, using polyoxometalate precursor or without any precursors, we have synthesized two offset sandwich-type compounds, Na5H [{Co(H2O)2}3W(H2O)2(B-β-SbW9O33)2]?11.5H2O (7) and Na4H4[{Ni(H2O)3}2 {W(OH)2}2{B-β-SbW9O33}2]?23H2O (8). Compounds 7 and 8 present offset sandwich structure based on [B-β-SbW9O33]9? building units, in which 7 construct 3D network-like framework with the linkage of Co2+ and Na+ ions.The compounds were characterized by IR, UV, XPS and EPR spectroscopy, single crystal X-ray structural analysis, and studied by TGA, CV, the variable-temperature magnetic susceptibilities.