The New Arsenic Molybdenum Polyoxometalate Synthesis And Characterization

The polyoxometalates is undergoing changes from the classical discrete structure to multi-function materials with the properties of optics, magnetic and chiral, etc. So researchers have always been interested in obtainning new compounds with novel structure and interesting properties. In this paper, the main work has been focused on the rare reported arsenomolybdates, and eight novel compounds have been synthesized by conventional or hydrothermal methods.molybdenum arsenate complexes with{AsMo7O27} subunits:(NH4)15[As2NiFe5Mo22O85(H2O)]·15H2O(1)(NH4)16 [As2Fe6Mo20080(H20)2]·18H20 (2)(NH4)17[As2Fe5Mo21O82]·14H2O (3)(NH4)25[As6Fe7Mo22O98].13H2O(4)molybdenum arsenate complexe containing central Ag(I) cation(NH4)14[AgAs5Mo15O60]·13H2O (5)organic-inorganic molybdenum arsenate complexes:[Ni(C8H7N3)3]2AsvMovMo11ⅥO40-4H2O(6)[Co(phen)2(H20)]2[As6CoMo6O30]-4H2O(7)multi-electron reduced sulfur molybdate compound((CH3)2NH2)6SMo4ⅤMo8ⅥO40 (8)These compounds are characterized by single-crystal X-ray analysis, IR analysis, elemental analysis, UV-vis analysis, fluorescence analysis, ESI-MS analysis and Magnetic analysis. Compounds 1-4 are novel molybdenum arsenate complexes based on {AsMo7O27} subunits. Compounds 1-3 display double-sandwich-like structures enwrapping transition metal cluster presenting ferromagneticcoupling. Compounds 2 and 3 have two transition metal ions in each central belt, which are different from the compound 1 with three transition metal ions. Compound 4 displays X-type structure, which is a novel single molecule magnet, presenting antiferromagnetic or ferromagnetic with the change of temperature. Compound 5 displays a fan-type structure based on{AsMo5O20} subunits, and a Ag(I) with sp2 hybrid entrapped in the center. Compounds 6 and 7 are organic-inorganic molybdenum arsenates, the polyoxoanion of compound 6 is the saturated Keggin type with one electronic reduction, the polyoxoanion of compound 7 is composed of the well-known A-type Anderson anion capped with the cyclic As3O6 trimers on opposite faces of the anion plane. Compound 8 was synthesized by conventional solution method, in which the Keggin sulfur molybdate was deeply reduced.