Synthesis, Crystal Structure And Third-order Nonlinear Optical Properties Of Cationic Iridium Complexes

Metal-organic complexes formed by metal centers and organic ligands through metal-carbon bonds,with their structural diversity and excellent physical and chemical properties,have important application value in bioanalysis,functional materials,catalysis and other fields.Under the rapid development of the information age,nonlinear optics produced by the combination of optics,physical chemistry,electronic information and material science have been greatly developed and applied,and materials with nonlinear optical properties play a very important role in many fields such as laser communication,medical devices,and optoelectronic devices.Metal-organic complexes have become a research hotspot in the field of nonlinear optical materials because of their material stability and good performance in nonlinear optics.Among the many metal-organic complexes,Iridium-containing metal-organic complexes exhibit excellent optical properties attributed to their special electronic structure and high photoluminescence quantum yield,higher photostability and short phosphorescence lifetime.Research shows that iridium metal-organic complexes have been found to have good third-order nonlinear optical effects.Iridium metal-organic complexes with different structures can be prepared by combining the central metal iridium with different types of organic ligands,and the structural modification of auxiliary ligands and chelating ligands can effectively adjust the HOMO-LUMO energy level of the complexes,thereby improving the nonlinear optical properties of iridium complexes and realize a wider range of applications.At present,cationic complexes are the main types of iridium containing metals with nonlinear optical properties.The synthesis strategy is to prepare iridium dichlorobridge compounds as precursors,and then react with different auxiliary organic ligands to prepare iridium organic complexes.In this paper,two precursors of iridium dichlorobridge compounds[（ptpy）₂Ir（μ-Cl）]₂ and[（ppz）₂Ir（μ-Cl）]₂ were synthesized from two different chelating ligand,while nine nitrogen-containing auxiliary ligands with different structures were also prepareed,and then 13 novel iridium metal-organic complexes 1-13 were synthesized by the coordination between iridium precursors and auxiliary ligands.All the complexes were cultured as crystals and their single-crystal structures were resolved.The third-order nonlinear optical properties of these complexes were tested by Z-scanning technology,while thermal stability and other optical properties were studied by thermogravimetric means,ultraviolet-visible and fluorescence spectroscopy.The relationship between the properties and structure of iridium metal-organic complexes was preliminarily discussed.1.Four halogen Schiff based iridium metal-organic complexes were synthesized from the reactions between nitrogen-containing auxiliary ligands with four different halogen functional groups and p-tolylpyridine precursors as building blocks.The molecular structures of iridium complexes were identified by single crystal X-ray diffraction,mass spectrum and other means.The third-order nonlinear optics properties,thermal stability and crystal structure of iridium complexes with Schiff base ligands containing different halogens were investigated.2.In addition,nine iridium metal organic complexes were synthesized by the reaction of iridium phenyl pyrazole precursors with halogen Schiff based ligands,pyridine methylene amine ligands,quinoline and quinazoline ligands,respectively.The third-order nonlinear optics properties and crystal structure of iridium complexes were studied by changing the structure of chelating ligand and auxiliary ligand.（1）[Ir（ppz）₂（pyphF）][PF₆]（2）[Ir（ppz）₂（pyphCl）][PF₆][CH₂Cl₂]（3）[Ir（ppz）₂（pyphBr）][PF₆][CH₂Cl₂]（4）[Ir（ppz）₂（pyphI）][PF₆][CH₂Cl₂]（5）[Ir（ptpy）₂（pyphF）][PF₆]（6）[Ir（ptpy）₂（pyphCl）][PF₆]（7）[Ir（ptpy）₂（pyphBr）][PF₆][CH₂Cl₂]（8）[Ir（ptpy）₂（pyphI）][PF₆]（9）[Ir（ppz）₂（DiphOPy）][PF₆][CH₂Cl₂]（10）[Ir（ppz）₂（DiphMePy）][PF₆]（11）[Ir（ppz）₂（DiphEthPy）][PF₆][CH₂Cl₂]（12）[Ir（ppz）₂（baqu）][PF₆]（13）[Ir（ppz）₂（phqz）][PF₆][CH₂Cl₂]...