| Over the years, people have paid more and more attention to the metal-organic coordination polymers due to their diversity and potential application. the synthesis and characterization of metal polycarboxylate coordination polymers has been inspired by these materials'applicability in diverse applications, such as gas storage, small molecule absorption and separation, ion exchange, catalysis, and luminescence.In this work we summarized the study of aromatic carboxylic acid complexes. We have synthesized fourteen complexes, and The coordination compounds have been synthesized and characterized by X-ray single crystal diffraction analysis, IR spectra, fluorescence spectroscopy, thermal analysis.There are three chapters in this dissertation:In the first chapter, the concepts, fundamental characteristics, principle of coordination chemistry and rare earth chemistry are systemically introduced, as well as the reseach significance and the results of this thesis.In the second chapter, four coordinate polymers were synthesized by using the [1,1'-biphenyl]-4,4'-dicarboxylic acid ligand. The complexes of [Mn(4,4'-BPA)(Phen)2]·4H2O (1),[Mn(4,4'-BPA)(Phen)2]·2H2O (2),[Cu(4,4'-BPA)(Im)6]·2H2O (3),[Zn(4,4'-BPA)(4,4'-bipy)]·4H2O (4) were obtained. The complexes 1-4 belong to Monoclinic crystal system, P2(1)/c space group, Triclinic crystal system, P-1 space group, Monoclinic crystal system, C2/c space group, Triclinic crystal system, P-1 space group respectively.The coordination environments of crystallographic independent Mn2+ ions in complexes 1 and 2 are the distorted {MnO4N2}octahedron, and The coordination environments of crystallographic independent Cu2+ in complex 3 is he distorted {CuN6}octahedron.These complexes have been characterized by infrared spectra (IR), X-ray single crystal diffraction, thermogravimetric analysis (TGA) and fluorescence properties.In complexes 1 and 2, two symmetry independent 4,4'-BPA ligands coordinate to the same Mn2+ center in bridging bis-monodentate mode to produce a translational one-dimensional Mn-4,4'-BPA chain with a Mn-Mn-Mn, complexe 3 is mononuclear complex. Complexe 4 is coordination polymer with porous structure.The hydrogen-bondings play an important role in the constructions of the complexes crystal structures.In the third chapter, nine coordination compounds were synthesized by using the [1,1'-biphenyl]-4,4'-dicarboxylic acid ligand and rare earth ions and zinc ion. The complexes of Y(3-pyrac)3(H2O)3 (5) , La(3-pyrac)3(H2O)3 (6) , Sm(3-pyrac)3(H2O)3 (7),Eu(3-pyrac)3(H2O)3 (8),Gd(3-pyrac)3(H2O)3 (9),Tb(3-pyrac)3(H2O)3 (10),Dy(3-pyrac)3(H2O)3 (11),Er(3-pyrac)3(H2O)3 (12),Zn(3-pyrac)2(H2O)2 (13) were obtained. These complexes 5-12, Ln(3-pyrac)3(H2O)3 [Ln = Y 5, La 6, Sm 7, Eu 8, Gd 9, Tb 10, Dy 11, Er 12), are isomorphous and crystallized in the hexagonal system, with space group R3, while the crystal system and space group of complexe 13 are Monoclinic, P2(1)/n respectively. The repeating unit of complexes 5-12, Ln(3-pyrac)3(H2O)3, consists of one Ln(Ⅲ) , three 3-pyridylacetates and three coordinated water molecules . The lanthanoid ion is nine-coordinated by two oxygen atoms from three 3-pyrac ligands and three oxygen atoms from three coordinated water molecules and has a distorted tricapped trigonal prismatic coordination polyhedron. The asymmetric units of complexes extend into a one-dimensional chain via hydrogen-bonding contact. However, the unit aggregates into two-dimensional layer via hydrogen-bonds. These 2D hydrogen bonding layers are further linked into 3D hydrogen bonding network by hydrogen bonds shown in the supporting information.In the fourth chapter, We have obtained one mononuclear complexe 14 by using the reaction of 6-(3,5-dimethyl-1H-pyrazol-1-yl) picolinic acid and FeCl2·4H2O. The complexe 14 belong to Triclinic crystal system, P-1 space group.These complexes have been characterized by infrared spectra, X-ray single crystal diffraction, thermogravimetric analysis and fluorescence properties.Structural analysis shows that the iron atom is coordinated with two oxygen atoms from the carboxyl group of the ligand together with four nitrogen atoms from the pyridine rings and pyrazole rings. Hydrogen bonding plays a very important role in the construction of this supramolecular architectures.The fifth chapter summarizes the achievements and defects systematically in the paper, and puts forward proposals and expectations in the future. |
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