Synthesis, Crystal Structure And Electro-optical Properties Of The Complexes With2-Pyridinecarboxaldehyde Schiff Base Transition Metal

Based on the concept of molecular design for the functional materials, combinedwith the fully the development and application of molecular wires，we do great dealof research in Schiff base field.The author choose the Hm-pba=3-N-（2′-pyridylimine）benzoic acid and Hp-pba=4-N-（2′-pyridylimine）benzoic acid with the Similarstructure.We also use the Kpmta=2-（2-pyridymethylamino）ethanesulfonate fivecoordination polymers of transition metal with these ligands.These crystals are alsocharacterized by using the single-crystal X-ray diffraction, the IR, the TGAexperiment, the UV-visible, the fluorescence techniques and quantum chemistrycalculate.Five crystals have been synthesized, the crystals bellowed:1.[V₃（m-pba）₄（OH^-）₆]·2ClO₄（1）；2.[Fe（m-pba）₂（H₂O）（azide）]·2ClO₄（2）；3.[Ni₂（pmta）₂（azide）₂]_n（3）；4.[Ni₂（p-pba）₂Cl₂（H₂O）₂]_n·2H₂O （4）；5.[Co（pmta）₂（azide）₂（H₂O）₂]·2H₂O （5）The single-crystal X-ray analysis shows that all the crystals’ group are Triclinic.The crystald of1and2space group are P2₁/n. The crystals of3and5space group areP2₁/c. The crystal of4space groupis is C2/c. The structure of crystallizes1,2and5isone, two and three central Island shape transition metal complex. The structure ofcrystallize3is infinite chain shape Ni coordination polymers, use the sulfonate as thebridging. The structure of crystallize4is infinite plane shape Ni coordinationpolymers, formed square pyramidal configuration.Except4the rest crystallizes areformed the distorted octahedron with six coordination. The face-to-face π–π the roleof stable constitute the layered structure of all the crystals’s group.Except thecoordination polymers are all with H—bond and molecule to molecule effect, theseeffect enhance the crystal’s stability.IR spectra showed that when pyridinecarboxaldehyde and its derivativescombine with transition metal, the characteristic functional groups of Coordination agent and its derivatives data happen specific change.Fluorescence spectrum analysis shows that except crystallize3emission andexcitation spectrum happen blueshift，the rest four crystallizes are happen redshift.The electronic structures and bond characteristics in six componud andcomplexs have been discussed by the ab-initio calculations with Hartree–Fork method.the quantum chemistry calculate take the complexes crystal structure as the model.Show that when pyridinecarboxaldehyde and its derivatives combine with transitionmetal, have two LUMO and HOMO orbital energy level，this in agreement with theUv–vis spectrums the ligands have only one absorption, but the complexes have twoabsorption in this area. Further proof the structure of complexes.The experiment calculation results show that,two coordination polymercrystallize3and4. Uv–vis spectrums and Kubelka–Munk shows that infinite chainshape crystallize3coordination polymers have semiconductor characteristics,but theinfinite plane shape crystallize4do not have.