Synthesis, Structures And Properties Of Metal-triazole Complexes

The potential applications of metal organic complexes in catalysis,gas adsorption,and photoelectric materials have attracted wide attention of chemists.In this thesis,3,5-bis?4-pyridyl?-1H-1,2,4-triazole?4,4'-Hbpt?was selected as main ligand to react with different transition metal ions under suitable conditions,and various metal-triazole complexes with different structures were obtained through regulating three kinds of auxiliary ligands?halogen,pseudohalogen,sulfate?.The work of the thesis mainly focus on the the synthetic reaction rules of metal-triazole complexes with the participation of auxiliary ligands,as well as the influence of auxiliary ligands on the structure and photoluminescence properties of the target products.The research results may provide theoretical guidance for the preparation of luminescent materials with practical values.1.Three metal-triazole complexes were synthesized by layer diffusion method with halogen ion as auxiliary ligand,[Hg?4,4'-Hbpt?Cl₂]_n?1?,[Hg?4,4'-Hbpt?Br₂]_n?2?,[Hg?4,4'-Hbpt?I₂]_n?3?.Their structures and properties were characterized by X-ray single crystal diffraction,X-ray powder diffraction,fluorescence spectroscopy,solid ultraviolet diffuse reflectance spectroscopy and thermal synthesis analyzers.Studies have shown that the three compounds display similar one-dimensional zigzag chain,while present different symmetry and space accumulation modes accompanying with the different radius of the terminal halogen ions.Three complexes exhibit same luminescence behaviors,and the original luminescence of them are all mainly contributed from the charge transfer of ligands to metals.While three complexes exhibit small differences in luminescence properties due to their different structures.2.Utilizing pseudohalogen ions as auxiliary ligands,five metal-triazole complexes were synthesized by layer diffusion or solvothermal method,{[Cd?4,4'-Hbpt??SCN?₂]·CH₃CN}_n?4?,{[Zn?4,4'-Hbpt??SCN?₂]·CH₃CN}_n?5?,[Zn?4,4'-Hbpt??SCN?₂]_n?6?,{[Co?4,4'-Hbpt?₂?SCN?₂?H₂O?₂]·H₂O]}_n?7?,{[Ni?4,4'-Hbpt?₂?SCN?₂?H₂O?₂]·2H₂O}_n?8?,and their structures and properties were systematically characterized.The studies found that complex{[Cd?4,4'-Hbpt??SCN?₂]}_n could not be achieved through the SCSC process of the complex 4 under vacuum extraction conditions.The presence of acetonitrile solvent molecules leads to the different orientation of chain structures in complexes 5 and 6,so the fluorescence emission peak of the complex 5 is blue-shifted about 6 nm as compared to complex 6.Complexes 7 and 8 are centrosymmetric mononuclear complexes,and both emit green fluorescence around 487 nm.3.Utlizingsulphateanionasauxiliaryligand,{[Cd?4,4'-Hbpt?SO₄?H₂O?]·0.5H₂O}_n?9?was synthesized by the layer diffusion method.Its structure and properties are characterized,and the luminescence experiments showed that the complex could emit blue-green fluorescence.