Rare Earth Complexes In The Design, Synthesis And Structure Of The Material Laser Materials

The development of laser technology has put forward higher demands for the research of new materials. In the past few decades, research of laser materials has been mainly focused on inorganic materials. They have excellent mechanical properties and are stable in environment but their NLO responses are not large.During the 1980s it became clear that two-photon pumped up-conversion organic materials might be a new choice for use in laser technology. It has some advantages other than inorganic materials, such as quick response, large electro-optical coefficient, wide transparence, simple manufacture, low cost and easy for integration, etc. Some pyridinium salts with "D-Ï€-A" structure have very excellent TPA and up-conversion fluorescence properties, so they are the possible candidates to be used to make TPA up-conversion dye lasers. However the drawback of organic materials is their poor stability.In this thesis, we try to incorporate functionality from both inorganic and organic components through the formation of hybrid organic-inorganic materials, and develop a new approach in synthesizing laser materials. The main points are summarized as follows:Two kinds of "D-Ï€-A" structure pyridinium salts with TPA activity are synthesized (L= trans-4-[p-(N, N-Dimethylamino)styryl]-N-acetate salt and L = trans-4-[p-(N-Methyl-N-(hydroxyethyl)amino)styryl] -N-acetate salt) . Then 33 rare earth complexes of 3 types (Ln1P, Ln1, Ln2) are synthesized. The approaches of synthesizing complexes are discussed. The choice of solvent is vital in growing crystals. Generally speaking, ethanol/water of 3/1 are used for series LnlP and Lnl. However, less water are used in synthesizing Ln2 because the poor solubility of L2 in water.Fortunately, 16 single crystals including two ligands and fourteen rare earth complexes were obtained. Crystal analysis shows that the structural characters of compounds in the same series are analogical.For series LnlP, the compounds crystallize in the Triclinic, space group Pi.Each unit contains one rare earth with three L and one 1,10-Phenanthroline as ligands. The three ligands are all coordinated in monodentate fashion.For Ln1 and Ln2 series, the compounds all crystallize in the Triclinic, space group Pi. They are all centrosymmetry molecules. There exists three coordination modes for ligand L: chelating, monodentate, bridging. The length of each molecule is almost 4 run.The linear and nonlinear optical properties of these compounds have been systematically studied. The following parts are included in this thesis: one-photon and two-photon fluorescence; upconversion superradiance and cavity lasing properties; the optical power limiting effect of these compounds; and so on. TPA absorption coefficients have been got by Z-Scan method. The relationships between structure and property are discussed.In conclusion, design, synthesis and properties of a series of laser materials have been systematically studied in the thesis.