| As a new type of functional crystal material,coordination compounds have incomparable advantages over conventional materials.Because the structure of complexes determines their properties,the design and synthesis of functional complexes with special structures and expected properties has always been of great interest to researchers.The reason why organic ligands such as nitrogen-containing heterocyclic and carboxylic acids have always been the focus of research in chemistry and materials science is that these organic ligands have many kinds,strong coordination ability of nitrogen/oxygen atoms and diverse coordination modes.They can be directionally designed with a variety of metal atoms or ions to coordinate compound materials with unique structures,and the organic ligands of polynitrogen have many properties.Metal complexes are more conductive to the research and application in optics,magnetic,semiconductor materials and so on.Based on the above considerations,a series of organic ligands of nitrogen heterocyclic and nitrogen heterocyclic carboxylic acids were designed and synthesized by hydrothermal solvent method and diffusion method.Their structures were determined by infrared spectroscopy,X-single crystal diffraction,elemental analysis,mass spectrometry,nuclear magnetic resonance.The properties of optical,magnetic,adsorptive and semiconductor were studied by solid-state fluorescence spectroscopy,solid-state ultraviolet diffuse reflectance spectroscopy,thermogravimetric and differential thermal analysis,and magnetic susceptibility.The mechanism of molecular energy transfer was studied by density functional theory?TDDFT?.Specific research contents are as follows:?1?A series of novel metal-quinoline carboxylic acid complexes have been synthesized by solvothermal method using 3-hydroxy-2-methylquinoline-4-carboxylic?HMCA?as the main ligand and different coordination modes between rare earth metals and transition metals.[PrCl?H2O?3?L??HL?]nnCl?1??[Zn?CH3OH?4?L?2]?2??[Ni?L?2?EtOH?2?MeOH?2]?3??[Cu?L??Phen??CH3OH?]?H2O??4?The structures were characterized by infrared spectroscopy,mass spectrometry,nuclear magnetic resonance,elemental analysis and single drystal structure.The properties were studied on photoluminescence and semiconductor,the energy transfer mechanism was studied by the time dependent density functional theory?TDDFT?.Four different crystal structures were obtained:complex?1?is monoclinic P2?1?space group 2-D chain structure;complex?2?is triclinic P1 space group 0-D structure;complex?3?is triclinic P-1 space group 1-D structure;complex?4?is monoclinic P2?1?/C space group 0-D structure.The photoluminescence spectra show that the complexes?1?are potential red photoemission materials;the complexes?2?are potential blue photoemission materials;the complexes?3?are potential green photoemission materials;and the complexes?4?are potential blue-purple photoemission materials.Solid-state diffuse reflectance spectra show that complex?1?has a wide optical band gap of 2.75 eV;complex?2?has a wide optical band gap of1.73 eV;complex?3?has a wide optical band gap of 2.25 eV;complex?4?has a wide optical band gap of 1.91 eV.All four complexes are good candidates for wide optical band gap semiconductor materials.TDDFT show that charge transfer of complex?2?is LMCT;charge transfer of complexes?3?is LLCT;and charge transfer of complex?4?is LLCT.?2?Two new rare earth mercury complexes[Ln?IA?3?H2O?2]n?Hg3Cl9?n·4nH2O?Ln=Eu?5?and Tb?6?;IA=isonicotic acid?were synthesized by hydrothermal method using isonicotic acid,HgCl2,EuCl3·6H2O and TbCl3·6H2O.Their properties and structures were characterized by photoluminescence,semiconductor,energy transfer mechanism,elemental analysis and single crystal X-ray diffraction.Crystal structure shows that both complexes are 3-D chains of triclinic P?space group;solid-state diffuse reflectance spectra show that complex?5?has 2.81 eV wide optical band gap;complex?6?has 3.47 eV wide optical band gap,both of which are good candidates for wide optical organic semiconductor materials.The photoluminescence spectra show that the complexes?5??6?are potential red and green photoluminescent materials,and their luminescent properties are further explained by energy transfer mechanism.?3?Three novel in-situ complexes[?N,N'-dimethyl-2,2'-bipy?2(Bi2Cl10)·2H2O?7?,?-CuCl4?N,N'-dimethyl-2,2'-H2bipy??8?,?-CuCl4?N,N'-dimethyl-2,2'-H2bipy??9?were obtained by in-situ reaction of 12/15 metal and 2,2'-bipyridine systems.The structures were characterized by IR,elemental analysis and single crystal X-ray diffraction.The photoluminescence properties,semiconductor properties and energy transfer mechanism were studied.Crystal structure shows that complex?7?is a 3-D chain structure of monoclinic P21/n space group;complex?8?is a 2-D chain structure of monoclinic C2/c space group;complex?9?is a 3-D chain structure of orthogonal Fdd2 space group.Photoluminescence spectra show that complex?7?9is a potential green photoluminescent material.TDDFT calculations show that charge transfer of complexes?7?9is all?LLCT?.?4?A series of lanthanide porphyrins,[LnIII?TPPS?IV]nnH5O2?Ln=La?10?,Sm?11?,Eu?12?;H2TPPS=tetra?4-sulfonatophenyl?porphyrin?,have been synthesized through solvothermal reactions And also a new zinc porphyrin complex[Zn2Cl4?5,10,15,20-tetra-?4-?triazol-1-yl?phenyl?porphyridine?]nnCl·nH3O·7nH2O?13?containing IIB has designed and synthesized by solvothermal technique using5,10,15,20-tetra-(4-?triazol-1-yl?phenyl ligand.The structures were characterized by IR,elemental analysis and single crystal X-ray diffraction.Crystal structure shows that the complexes?10?12are tetragonal P4/mcc space group 3-D chain structure,and the complexes?13?are orthogonal Pmmn space group 1-D chain structure.The adsorption capacity of CO2 indicated that the complexes?10?12were 0.9 mmol/g,1.2 mmol/g and 1.9 mmol/g,respectively.All of them had good adsorption capacity for CO2.The magnetic properties show that complex?10?is a good potential ferromagnetic material,complex?11?is a good potential antiferromagnetic material,and complex?12?is a good potential paraferromagnetic material.The solid-state diffuse reflectance spectra show that the optical band gap of complex?13?is 1.60 eV,which has good potential for semiconductor materials.Photoluminescence studies show that complex?13?is a potential green photoluminescent material.TDDFT show that the photoluminescence of complex?13?is attributed to the charge transfer of?-?*.?5?A series of novel three complexes[Zn3?2,2'-bi-1H-imidazole?2?1H-biimidazole?2?SO4?2]n?14??{[Cd?2,2'-biim??4,4'-bipy??H2O??ClO4?]?ClO4?}n?15??[CdCl2(C13H12NO2)]n?16?(C13H12NO2=N-methyl-4-pyrid-3-ylbenzoic acid)have been synthesized through solvothermal reactions using 2,2'-biim,4,4'-bipy,2,2'-bi-1H-imidazole?4-pyridyl-3-benzoic acid ligand and IIB metal.The structures were characterized by infrared spectroscopy,mass spectrometry,nuclear magnetic resonance,elemental analysis and single drystal structure.The crystal structure shows that the complex?14?is a monoclinic C2/c space group 3-D chain structure;the complex?15?is an orthogonal Pna21 space group 3-D chain structure;and the complex?16?is a monoclinic P21/c space group 1-D chain structure.Photoluminescence spectra show that complex?14?is a potential blue photoluminescent material,complex?15?is a potential green photoluminescent material,and complex?16?is a potential blue photoluminescent material.TDDFT show that the luminescent nature of complex?14?16is LLCT.Solid-state diffuse reflectance spectroscopy shows that the optical band gaps of complex?14??15?are2.08eV and 3.25eV,respectively,and they are all candidate materials for high-efficiency optical bandgap semiconductors.?6?Two novel two-dimensional layered photoluminescent complexes[CdBr2?C4H4N2?]n?17?,?C6H5N2??FeBr4??18?were synthesized by pyrazine or cyanopyridine as one of N-donor ligands and Gd?II?and Fe?III?atoms of IIB group.The complexes were characterized by infrared spectroscopy,mass spectrometry,nuclear magnetic resonance,elemental analysis and single drystal structure.The crystal structure shows that the complex?17?is a 2-D chain structure of the orthogonal C222 space group and the complex?18?is a 3-D chain structure of the triclinic P?space group.The photoluminescence spectra show that the complex?17?is a potential green light emission spectral material and the complex?18?is a potential purple light emission spectral material.TDDFT was used to reveal the luminescence mechanism of complexes.The charge transfer of the complex?17?is attributed to the interaction of MLCT and LLCT,and the charge transfer of the complex?18?is attributed to LMCT. |
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