Synthsis, Crystal Structure Of Ethylpyridyl Ether Derivatives/Zincous Complexes And Studies On Nonliear Optical Properties

Nonlinear Optical (NLO) materials have extensive applications in the high-speed developing information industry, and they play a more and more important part in the application areas of frequency-changing, laser modulation and deflexion, and Q switch and so on. So it is very important for the light-signal processing, transferring and operation and so on to research NLO materials. Based on the flexibility of organic molecule structure, we picked 4-Nitro-1-Oxide-Pyridine-2-Carboxylic Acid(POA) as a mother reagent to prepare and synthesized 6 crystal materials through solution growth technique, in fitting of the requirements for NLO materials from the relationship between molecular structure and material function. The grown 6 crystals were characterized using Element analysis, Single-crystal X-ray diffraction, FTIR, UV-visible, DSC-TGA, Fluorescence, SHG studies.Crystal 1, 2 and 3 are Ethylpyridl ether derivatives, and crystal 4 and 5 are complexes, and crystal 6 belongs to pyridine dicarboxylic acid. Single-crystal X-ray analysis shows, crystal 1, 2, 6 and complex 4 have plane-structure, and crystal 1 and 2 have the similar noncentrosymmetrical structure, and complex 4 and 5 have five-coordination structure, and the packing arrangement with intermolecular hydrogen bonds of crystal 2 is two-dimensional structure but one-dimensional structure in crystal 2, 3 and 6 is formed through the intermolecular hydrogen bonds, and there is a one-dimensional structure in complex 5 through an atom of O in carboxyl and an intramolecular hydrogen bond. FTIR analysis shows that the stretching and bending peaks of N-H and the stretching peaks of C=O in complex 4 and 5 disappear. UV-visible analysis shows that absorbing peaks of crystal 6 have red-shift phenomenon compare to that of crystal 1, 2 and 3 with the similar absorbing peaks and that there is a higher cutoff ultraviolet-visible absorption of crystal 6 than that of crystal 1, 2 and 3. DSC-TGA analysis shows that the stability of crystal 6 is 30℃higher than that of POA but the stability of crystal 1, 2 and 3 is lower than that of POA and that the decomposition temperature of framework molecular of complex 5 is higher than that of complex 4. Fluorescence analysis shows that emission peak of crystal 6 has blue-shift phenomenon compare to that of POA and crystal 1, 2 and 3 have the similar excitation and emission peaks, and that emission peak of complex 4 has red-shift phenomenon compare to organic ligand. SHG studies shows that SHG efficiency of crystal 1 is about 2 times as large as that of KDP and that crystal 2 has weak SHG efficiency.