| In this thesis, several supermolecular compounds based on classical polyoxometalates(POMs) and transition metal complexes with triethylene tetramine and phenanthroline havebeen synthesized via self-assembly under hydrothermal reaction conditions, and characterizedby IR, XPS, TG-DTA and variable temperature magnetic susceptibility. The physical andchemical properties of these compounds, such as thermal stabilities, magnetic behaviors andcatalytic activity, have also been researched in detail. These compounds are below:[CoⅢ(phen)3]2[{(CoⅡW12O40)CoⅡ(phen)2(H2O)}2CoⅡ(C3H10N2)2]·4H2O ( 1 ) in thespace group P21/n of the monoclinic system with a=18.164(5) A, b=23.619(5) A, c=22.780(5)A, β=110.094(5)°, V=9178(4) A3, Z=2。[CoⅢ(phen)3]2[{(ZnW12O40CoⅡ(phen)2(H2O)}2CoⅡ(C3H10N2)2]·2H2O (2) in the spacegroup P21/n of the monoclinic system with a=18.210(4)A, b=23.592(5) A, c=22.932(5)A,β=110.31(3)°, V=9239(3)A3, Z=2。[Ni(phen)3][(H2W12O40){Ni(phen)2H2O}{Ni(trien)}]·2H2O (3) in the space groupP21/n of the monoclinic system with a=18.0998(6)A, b=23.6504(8) A, c=22.9199(7)A,β=110.2220(10)°, V=9206.5(5)A3, Z=4。[Cu(phen)2]4[W(10O(32] (4) in the space group C2/c of the monoclinic system witha=25.047(3)A, b=16.613(3)A, c=23.447(5)A, β=90.19(3)°, V=9757(17)A3, Z=4。All these crystal structures are in low symmetric crystal system: Monoclinic, which maybe explained from the structures of spherical inorganic POM anions and plane organicphenanthroline. All these compounds have 0-D structure. Compound 1 and 2 have the samestructure. Two Keggin subunits are linked through one [CoII(C3H10N2)2] fragment andsupporting two [CoII(phen)2(H2O)] fragments on the other side, at the same time, [CoIII(phen)3]cations are placed around the Keggin subunits. Compound 3 consists of a pseudo Kegginsubunit and two kinds of supported nickel complexes, [Ni(phen)3] cations are also around theanions. Compound 4 is a Lindqvist-type isopolytungstate derivative with [Cu(phen)2] ascations. The triethylene tetramine as one of the reaction materials doesn't appear in the finalproduction but acts as reducing agent to reduce WVI to WV.Multiple intermolecular interactions drive the supramolecular assembly processes ofthese compounds. Phenanthroline with good π-electron conjugated system may lead themoiety to forming 1-D chain. There exist hydrogen bond interaction between polyoxoanionswith abundant oxygen on the surface and water molecules, and the interaction makesmolecules spread in 3-D space. The anions and cations array regularly according to theelectrostatic interaction. Most of the compounds mentioned in this thesis have theseinteractions and form 3-D suparmolecular structure.Compound 1 and 2 have several magnetic centers, but the data of magnetic susceptibilityshows every center is isolated. Decatungstates show good catalytic activity in many reactions,so primary research in decolorizing dye was performed on compound 4. Compared somesimilar reactions with other polyoxometalates as catalyst, the result shows this decatungstatedoesn't suit to this reaction. |
PDF Full Text Request