Syntheses, Structures And Properties Of The New Metal-oxygen Clusters

In this paper, by the applications of hydrothermal technique, through the use of a metal element (W) acid (salt) or oxides, selecting the appropriate organic ligands as well as the second transition metal salts, controlling the temperature and pH of reaction system, we synthesized a series of polyoxometalates with novel structures and interesting properties. The structures of all the compounds have been characterized by elemental analyses, IR spectra and X-ray diffraction analyses, some compounds have been characterized by UV-Vis and XPS spectra.In this paper,6new metal oxygen clusters were synthesized.Ⅰ.Tungsten-oxygen clusters containing ligands of1,10’-phen and2,2’-bpyBy the applycation of hydrothermal synthesis technology, we synthesized four tungsten-oxygen clusters. Single crystal structure analysis reveals that the asymmetric unit of compound1consists of one [BW12O40]5-anion, two TMCs [Cu(bpy)(phen)]+and three TMCs [Cu(bpy)2]+. In compound2,the formula of the POM is [SiWⅥ12O40]4-. Thus, there contain four Cu+TMCs:[Cu(2)(bpy)2]+,[Cu(3)(bpy)2]+,[Cu(4)(bpy)2]+and [Cu(1)(bpy)(phen)]+. Compound3contains [GeW12O40]4-ions and four [Cu(phen)2]+TMCs. Compound4contains [GeW12O40]4-ions and four [Cu(2,2’-bpy)2]+TMCs. All the compounds exhibit an unusual3-D supramolecular network structure through the N-H...O hydrogen bonding interactions or the π...π interactions.Ⅱ. Tungsten-oxygen clusters containing ligands of bpy(phen) and iso-Nicotinic acidBy the applycation of hydrothermal synthesis technology, we synthesized two tungsten-oxygen clusters. Single crystal structure analysis reveals that compounds5and6contain a pseudo-Keggin [H2GeW12O40]2-and a Keggin [AsW12O40]5-anions, respectively. And compound5and6have intersing TMCs which contain the ligand of iso-Nicotinic acid.