The Study Of Multicarboxylate Inorganic-Organic Hybrids Based On Polyoxometalates

The aim of this thesis is to synthesize inorganic-organic hybrid compounds with novelty structure by using main group, transition-metal, rare-earth element and Keggin and Anderson polyoxometalates, and multicarboxylate ligands, to study the synthetic conditions and rules for these compounds, to analysis the relationship between structures and properties and then to enrich polyoxometalate chemistry.In this paper, 23 new inorganic-organic hybrid compounds based on polyoxometalate building blocks have been synthesized under aqueous synthesis technique, and characterized structurally by elemental analyses, IR, TG and single crystal X-ray diffractions. The magnetic and fluorescence properties of some compounds have been studied.1. Under aqueous synthesis condition, nine new inorganic-organic hybrid compounds based on [BW₁₂O₄₀]^5- and [SiW₁₂O₄₀]^4- clusters and main group- multicarboxylate coordination complexes have been synthesized and characterized:（NH₄）₄（H₃O）[Ca₂Na₂（H₂O）₁₄（HDCTA）₂( BW₁₂O₄₀)]·3H₂O （1）（NH₄）₄（H₃O）[Sr₂Na₂（H₂O）₄（μ-H₂O）₂（HDCTA）₂( BW₁₂O₄₀)]·7H₂O （2）（NH₄）₄（H₃O）[Sr₂K （HDCTA）₂（H₂O）₁₄][SiW₁₂O₄₀]·H₂O （3）（NH₄）₄[Na₂（H₂O）₁₂][Al（DCTA）]₂[SiW₁₂O₄₀]·9H₂O （4）（NH₄）₆[Pb₃（H₂O）₂（DCTA）₂][SiW₁₂O₄₀]·8H₂O （5）[Na₆Bi₂（H₂O）₂2（DCTA）₂][SiW₁₂O₄₀]·2H₂O （6）（NH₄）₄[Ba（DCTA）₂（OH）₂SiW₁₂O₄₀]·8H₂O （7）[Ca₄（H₂O）₂4（H₂DCTA）₂][SiW₁₂O₄₀]·8H₂O （8）（NH₄）₅[Ca3（H₂O）₁₀（HEGTA）₂( BW₁₂O₄₀)]·3H₂O （9） DCTA= Diaminocyclohexanetetraacetic acidIn the compounds, main group elements may accept electron pairs provided by POM and DCTA, forming coordination polymer chain POM-M-DCTA。More surface charges of BW₁₂O₄₀^5- than that of SiW₁₂O₄₀^4- gives BW₁₂O₄₀^5- stronger coordination ability.2. Under aqueous synthesis condition, ten new inorganic-organic hybrid compounds based on [BW₁₂O₄₀]^5- and[Cr（OH）₆Mo₆O₁₈] ^3- cluster with transition-metal multicarboxylate bridging ligands have been synthesized and characterized:[{Cu₄（EGTA）₂（H₂O）₄}{Cu₂（H₂O）₈(SiW₁₂O₄₀)}]·14H₂O （10）（NH₄）₅[Cu₄（EGTA）₂（H₂O）₄(BW₁₂O₄₀)]·4H₂O （11）（NH₄）₆[Cu₂K2Na（H₂O）₂（DCTA）₂(BW₁₂O₄₀)]·5H₂O （12）（NH₄）₇[Cu₂（H₂O）₂（HDCTA）₂][β-Mo₈O₂₆]·14H₂O （13）[K₃（H₂O）₁₂{Cu₂（EGTA）（H₂O）₄Cu（H₂O）₆Cu₄(GeW₉O₃₃)₂}]·16 H₂O （14）（NH₄）₂[Zn₅（DCTA）₂（H₂O）16][SiW₁₂O₄₀]·8H₂O （15）（NH₄）₄[Cd₄（DCTA）₂（H₂O）₈][SiW₁₂O₄₀]·6H₂O （16）（NH₄）3[Ni₄Na（H₂O）₈（DCTA）₂][SiW₁₂O₄₀]·15H₂O （17）Na₃[Zr（EDTA）（H₂O）₂]₂[Cr（OH）₆Mo₆O₁₈]·10H₂O （18） EGTA = Ethyleneglycol-bis-（2-aminoethylether）-tetraacetic acid, EDTA = Ethylenediaminetetraacetic acidIn these compounds transition metal ions and multicarboxylates exhibit a coordination versatility. Compared with main group elements, transition metal ions have more tendency of forming multinuclear complex. The compound 18 is the first example of Zr（Ⅳ） complex-polyoxometalate compounds. The variable temperature susceptibility of 10 shows a weak antiferromagnetic interaction between Cu²⁺ ions and its emission spectrum attributed to the charge transfer between metal and ligand （LMCT）。3. Under aqueous synthesis condition, five new inorganic-organic hybrid compounds based on [SiW₁₂O₄₀]^4- and [Cr（OH）₆Mo₆O₁₈] ^3- cluster with rare-earth element and multiamino-multicarboxylate EDTA and DCTA have been synthesized and characterized:[Ce₃（HEDTA）₂（H₂O）9][Cr（OH）₆Mo₆O₁₈]·13H₂O （19）（NH₄）₂[Y₂（H₂DCTA）₂（H₂O）₁₂][SiW₁₂O₄₀]·6H₂O （20）（NH₄）₂[Sm₂（H₂DCTA）₂（H₂O）₁₂][SiW₁₂O₄₀]·8H₂O （21）（NH₄）₂[Er₂（H₂DCTA）₂（H₂O）₁₂][SiW₁₂O₄₀]·4H₂O （22）（NH₄）₂[Eu2（H₂DCTA）₂（H₂O）₁₂][SiW₁₂O₄₀]·10H₂O （23）In compound 19, Ce（Ⅲ） ion is ten-coordinated and connects with Anderson anion and EDTA, forming a layer structure. In compounds 20-23, Sm、Er、Eu and Y are eight-coordinated and accept only oxygen atoms of one carboxyl group of DCTA, forming isolated dinuclear complexes. The reason for this phenomenon may be 1)different ionic radii of rare earth elements. From Ce to Er the ionic radii decrease and then the coordination number of RE ionsdecrease. 2) different shape and size of POM. Anderson-type POM has a flat shape and a small size compared with Keggin anion, producing a limitted spacial encumbrance when coordinating to RE with DCTA; on the other hand, in Anderson-type POM the MoO6 octahedron has two terminal oxygen atoms and then a stronger coordination ability。...