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As a new type of optical, electrical, magnetic, and catalytic functional materials,metal-organic coordination polymers not only have chemical stability and highthermal stability like inorganic compounds, but also have easy modification,function, and structural diversification like organic compounds. Moreover, it hasreceived great attention from domestic and foreign scholars due to the potentialapplications in the fields of molecular adsorption and separation, molecularrecognition, and ion exchange.In this study, seven aromatic dicarboxylic acids as biphenyldicarboxylic acid,pyridinedcarboxylic acid, and imidazoledicarboxylic acid, which have differentcoordination sites are selected as main ligands, phenanthroline and isonicotinic acidare employed as auxiliary ligands, three new gallium complexes have beenhydrothermally synthesized. On the basis of the gallium complexes, different metalsources and aromatic dicarboxylic acid ligands （single pyridine ring→singlebenzene ring→double benzene rings→benzimidazole double ring） are selectedto design and synthesize one two-dimensional （2D） gallium coordination polymer,five indium coordination polymers, and four copper and manganese coordinationpolymers under hydrothermal and solvothermal conditions. They are structurallyanalysized by X-ray single crystal diffraction, elemental analyses, IR, and1H NMRspectroscopy, and properties researched by thermal gravimetric （TG） analyses, UVabsorption, solution and solid fluorescent analyses. The influence of syntheticconditions on the crystal structures has been analysized, and the relationshipbetween crystal structures and luminescent properties has been studied.（1） Three new gallium complexes based on pyridine-2,6-dcarboxylic acid（2,6-H2PDA）[Ga（2,6-PDA）2][Ga（2,6-PDA）（phen）（H2O）]·4H2O （1, phen=phenan-throline）,[Ga（2,6-PDA）2][H2IN]·2H2O （2, HIN=isonicotinic acid）, and [Ga（2,6-PDA）（OH）（H2O）]2（3） have been hydrothermally synthesized by strictly controllingof the pH value of the solution. Single crystal structural analyses reveal thatcomplex1contains mixed ligands,2has mononuclear structure, and3exhibitsdinuclear structure (distances of Ga3+ions is3.0061（3）). Based on them, a new2D gallium coordination polymer constructed by2,4’-biphenyl-dicarboxylic acid（2,4’-H2BPDA） with parallelogram channels has been designed and synthesized as[Ga（2,4’-BPDA）（OH）]n（4）. TG analyses reveal that the new gallium complexes allhave good thermal stability. Solid state luminescent analyses reveal that galliumcomplexes13have good monochromatic light and high intensity, which can beused as potential blue light materials. Gallium coordination polymer4exhibits green-blue emission, which can be used as potential green-blue light materials.（2） Based on the gallium complexes and coordination polymer, main groupmetal indium and biphenyldicarboxylic acid ligands with different coordination sitesare selected, two new1D chained and2D layered indium coordination polymers[In（2,2’-BPDA）（phen）Cl]n（5） and [In（1,3-BDC）（1,3-HBDC）·2DMF]n（6, DMF=N,N-dimethylformamide）, which are constructed by2,2’-biphenyldicarboxylic acid（2,2’-H2BPDA） and1,3-benzene-dicarboxylic acid （1,3-H2BDC）, respectively, and4,4’-biphenyldicarboxylic acid （4,4’-H2BPDA） tuned three new indium coordinationpolymers [In（4,4’-BPDA）1.5（phen）]n（7）,[In（4,4’-BPDA）（OH）（H2O）]n（8）, and[In（4,4’-BPDA）2·Me2NH2·H2O]n（9, Me2NH=dimethylamine） have been designedand synthesized under hydrothermal and solvothermal conditions. Topologicalstructural analyses reveal that complex5has1D helical chain structure modified byphen,6possesses （4,4） topological structure,7has unique2D trapezoid-like layerstructure,8has4-connected3D open-framework, and9possesses a two-foldinterpenetrating diamond-like3D network. Solid state luminescent analyses revealthat indium coordination polymers have high intensity emission and wide emissionrange from blue to orange-red light regions, which can be used as potential whitelight-emitting materials.（3） Four copper and manganese coordination polymers have been synthesizedunder solvothermal conditions and formulated as [Cu（4,5-HImDC）（phen）]n（10,4,5-H3ImDC=4,5-imidazoledicarboxylic acid）,[Mn（2,4’-BPDA）（phen）（H2O）]2n（11）,[Mn（4,5-HImDC）（phen）]n（12）, and [Mn（5,6-HBImDC）（H2O）]n（13,5,6-H3BImDC=benzimidazole-5,6-dicarboxylic acid） in the presence of imidazoledicarboxylic acids.Crystal structural analyses reveal that complex10has1D helical chain structure,11is dinuclear1D chain constructed by2,4’-H2BPDA,12has similar strcture with10but the coordination modes of central metal ions and ligands are different,13has2Dlayered structure constructed by double helical chains.（4） The syntheses experiments of aromatic dicarboxylate main group gallium/indium complexes and coordination polymers reveal that different molar ratios,reaction temperature, reaction time, and pH value of the solution play decisive roleson the crystal structures.（5） The relationship between crystal structures and luminescent propertiesreveals that the dimension of complexes, the distances between the metal ions andplanes, the dihedral angle of ligands, and the coordination modes of ligands haveimportant influences on the luminescent properties.
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