| Metal-Organic Frameworks(MOFs)are a class of crystalline materials with rich pore structures constructed by self-assembly of central metals or clusters and organic ligands.There are generally two types of stable MOFs:one is constructed from high-valent metal ions(hard Lewis acids)and organic carboxylic acid ligands(hard Lewis bases),and the other is constructed from low-valent transition metal ions(soft Lewis acids)and Azo salt-based ligands(soft Lewis bases).In the present mster thesis,based on the basic principle of the stability of MOFs,new coordination complexes with novel structures and rich pore structures have been hydrothermally synthesized by using flexible N-heterocyclic ligands of Na N3,4-cyanopyridine,3-pytz as main ligands,and organic carboxylic acids of3,5-pyridinedicarboxylic acid,and 5-nitroisophthalic acid.Organic carboxylic acid ligands such as formic acid,5-aminoisophthalic acid,2,5-furandicarboxylic acid,2,5-thiophene dicarboxylic acid,1,3,5-benzenetricarboxylic acid as auxiliary ligands,coordinated assembly with transition metal ions of Co(?),Mn(?),Zn(?),Pb(?),Mo(?),and rare-earth ion Pr(?).In this thesis,11 kinds of crystals have been synthesized by hydrothermal synthesis,and single crystal X-ray diffraction analysis and property research have been performed.The main results are as follows:(1)A series of complexes with similar structures of{[Pr2(C8H3O6N)(SO4)2]·5H2O]}n(1),{[Pr2(C8H3O6N)(Cl O4)2]·5H2O]}n(2),{[Zn4(C6O5H2)4·12(H2O)]}n(3)and{[Pb2(C9O6H4)·2(H2O)]·3H2O}n(4)have been synthesized by using5-nitroisophthalic acid,2,5-furandicarboxylic acid,1,3,5-benzenetricarboxylic acid and inorganic salts and their structural characteristics and basic properties were tested.Among them,complexes 1 and 2 are similar in structure,both of which have a three-dimensional network structure with a binuclear structure.1D double-stranded structure and interpenetrating structure exist in the crystal.In complex 3,Zn(?)and 2,5-furandicarboxylic acid forms a plurality of 1D chain structures.These 1D chain structures and water molecules form a layered structure through intra-and intermolecular hydrogen bonding.Complex 4 has a binuclear structure,and each Pb(?)center constitutes a coordination configuration with a triple triangular prism geometry,and a 1D double-stranded structure also exists in the complex.BET adsorption characterization of complex 1 was performed on N2and CO2,and the results showed that CO2 was selectively absorbed by complex 1.The fluorescence test of complex 1 showed that there existed?*-?transitions of electrons and?-?*transitions of rings.(2)A series of complexes with similar structures of{[Co(C6H4N5)2(H2O)4]·2H2O}n(5),{[Co2(TDC)2(3-pytz)2(H2O)]·4DMF}n(6)and{[Mn(C8H5NO4(H2O)]·2H2O}n(7)have been synthesized by using5-aminoisophthalic acid,5-nitroisophthalic acid,2,5-thiophene dicarboxylic acid and3-pytz and their structural characteristics and basic properties were tested.Among them,complex 5 has abundant hydrogen bonds,and repeating units and water molecules form a 3D structure through intra-and intermolecular hydrogen bonds;complex 6 has interpenetrating structure;complex 7 has1D chain structures and these chains and water molecules build a 3D network structure through hydrogen bonding.The N2 BET adsorption characterization of complex 6 was performed,and the results showed that the adsorption efficiency of complex 6 to N2 was poor.Fluorescence test was performed on complex 6,and the results showed that there were?*-?or?-?*transitions of electrons in this complex.(3)There are two complexes being synthesized by using 5-aminoisophthalic acid and 3,5-pyridinedicarboxylic acid,espectively:{[(C8H5NO4)·(H2O)]}n(8);{[(C12H8N6)]}n(9),and their structural characteristics and basic properties were tested.Among them,there are a large number of hydrogen bonds in complexes 8 and 9,and3D structure is built by intermolecular and intramolecular hydrogen bonds.(4)Inorganic salts 10 and 11 were also synthesized due to the decomposition of organic ligands,respectively:{[(Mo N9)3]}n(10);{[(C3H3Mn O6)3]}n(11),and their structural characteristics were tested. |
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