Syntheses, Crystal Structures And Thermal Stability Of Metal-Organic Complexes Based On Aromatic Polycarboxylic Acids

Due to the high specific surface area, channel-controllable, diverse structures and easy tobe functionalized, the metal-organic complexes show the unique properties and have goodapplication prospect in non-linear optical materials, magnetic materials, adsorption andseparation, luminescence and catalysis, etc. In the construction of metal-organic complexes,the aromatic polycarboxylic acids ligands with strong coordination ability and richcoordination modes have been obtained more attention.In this thesis,13metal-organic complexes based on aromatic polycarboxylic acids,pyridine ligands and transition/rare earth metal ions have been constructed via the diffusionand hydrothermal methods and characterized by single crystal X-ray diffraction, elementalanalysis, IR spectroscopy and thermal analysis. The experimental contents and results are asfollows: 1. Three complexes of [Cu（TBTA）（bipy）₃]_n（1）,[Zn（TBTA）（bipy）₃]_n（2） and[Cd（TBTA）（bipy）₃]_n（3） based on2,3,5,6-tetrabromoterephthalic acid （H₂TBTA）, bipy andtransition metal ions [Cu（II）, Zn（II） and Cd（II）] have been synthesized. The complex{[Tm（TBTA）_1.5（2,2-bipy）（H₂O）₂]·H₂O}_n（4） based on H₂TBTA,2,2-bipy and rare earth metalions Tm（III） also has been constructed under the same condition. The analyses of thecomplexes show that the complexes1-3are one-dimensional zigzag chain structure, thecomplex4is two-dimensional wave-like layer network. Compared with the complex4, thecomplexes1-3have good thermal stability, their first decomposition temperatures are allabove175℃.2. Four complexes,{[Zn（TBTA）（phen）₂]·H₂O·CH₃OH}_n（5）,{[Mn（TBTA）（phen）₂]·H₂O·CH₃OH}_n（6）,{[La（TBTA）_1.5（phen）₂（H₂O）]·2H₂O}_n（7） and{[Ce（TBTA）_1.5（phen）₂（H₂O）]·H₂O}_n（8）, based on H₂TBTA,1.10-phenanthroline （phen） andtransition/rare earth metal ions [Zn（II）, Mn（II）, La（III） and Ce（III）] have been synthesized.The complexes5and6are one-dimensional chain, while7and8are two-dimensional layernetwork. The thermal analyses confirm that the complexes5-8have poor stability with thedecomposition temperature about100℃. 3. Three complexes,{[Cu（TBTA）（Im）₃]·H₂O}_n（9）,{[Ni（TBTA）（Im）₃]·H₂O}_n（10） and{[Co（TBTA）（Im）₃]·H₂O}_n（11）, based on H₂TBTA, imidazole （Im） and transition metal ions[Cu（II）, Ni（II） and Co（II）] have been constructed. The analyses of the complexes show theyare allomerism. The complex9is one-dimensional zigzag chain structure and less stable withthe decomposition temperature at142℃.4. Two binuclear complexes of {[La2（BTA）_1.5（H₂O）₄]·3H₂O}_n（12） and{[Eu2（BTA）_1.5（H₂O）8]·6H₂O}_n（13） based on1,2,4,5-benzenetetracarbonic acid （H₄BTA） andrare earth metal ions [La（III） and Eu（III）] have been synthesized. The structural analyses ofthe complexes show that both of them are three-dimensional network, the diversecoordination modes of BTA^4-play a key role in constructing complex structure.