| Ten new novel complexes have been synthesized by the hydrothermal reaction of Co（Ⅱ）and Fe（Ⅱ） with Pyrazine-2,3-dicarboxylic acid, Imidazole-4,5-dicarboxylic acid etc.Complexes （1）-（10） were obtained single crystals. Complexes were characterized by singlecrystal X–ray diffraction, surface photovoltage spectroscopy （SPS）, IR spectra and UV–Visspectra, discussed the relations structure and photo-electric properties of complexes,comparative analysis of the SPS and UV-Vis, obtain some regularity results. In addition, Inorder to better contrast and study photo-electric properties of the complexes, in thearrangement of teacher, other students of our group synthesized several correlative complexes（not published）（complexes （11）-（18）） were tested X-ray powder diffraction（XRD）,thermogravimetric analysis（TG）. Investigate their relationship with SPS. Then wecomparative analysis of different complexes photo-electric properties conversion, especiallyutilize ray radiation scope and photo-electric conversion efficiency. The molecular formulasare as follows:（1）[Co（2,3-pzc）·2H2O]n·2nH2O （11）[Co（o-phta）（Pz）2]n（2）[Co（HImbc）2·（H2O）2]（12）[Co（PTA）2（Imh）2]·（PTA）·H2O（3）[Co（2-pdc）3·H2O]（13）{[Co（pdc）2（H2O）]·（Pz’）·2H2O}n（4）[Co（3-pdc）2·（H2O）4]（14）[K2Co2（ox）（btec）（CH3OH）2]n（5）{[Fe（Hpdc）2（H2O）2]·2H2O}（15）{[Ni（bipy）（H2O）4]·（bdc）}（6）[Fe（HImbc）2·（H2O）2]（16）[Ni（PhCOO）（phen）（H2O）3]·（PhCOO）（7）[Fe（pdc）·（H2O）2]n·n H2O （17）[Ni（dcpz）（H2O）4]（8）[Fe（ox）·（H2O）]n（18）[Ni（pic）2（H2O）2]（9）[â… Cdâ…¡0.25Cd0.5Na0.5（btec）0.5（H2O）2]n（10）[â… Cdâ…¡Cd （btec）]n·5H2O（2,3-pzc=Pyrazine-2,3-dicarboxylic acid，Imbc=Imidazole-4,5-dicarboxylic acid，2-pdc=pyridine-2-dicarboxylic acid，3-pdc=Nicotinic acid，H2pdc=pyridine-2,5-dicarboxylic acid,H2（ox）=oxalic acid, H4btec=1,2,4,5-benzenetetracarboxylic acid, H2-phta=o-phthalic acid,Pz=pyrazole, HPTA=Phonyl-toluic acid, Pz’=piperazine, Imh=tmidazole, H2bdc=m-phthalicacid, PhCOO=benzoate, H2dcpz=pyrazole-3,5-dicarboxylic acid, Hpic=2-pyrazinecarboxylicacid, bipy=2,2’-bipyridine, phen=1,10-phenanthroline） We emphatically adopt the SPS method to explore photo-electric properties of thecomplexes. Then they were compared and analysis with their UV–Vis. The results are listedas follows:1. Brief introduction of complexes structure:â‘ A series of Co complexes, Complexes （1）,（2） and （4） are Co（Ⅱ）, complexes （3） isCo（Ⅲ）, the complex （1） is1D infinite chain bridged by2,3-pzc. Complex （2）,（3） and （4） ismononuclear complexes, further bridged to3D infinite structure by hydrogen bonds.Complexes （11）-（14） are Co（Ⅱ） polymers and supramolecles. Complex （11） is1Dcoordination polymer bridged by o-phta and further connected into2D supramolecule byhydrogen bonds. Complex （12） is a mononuclear complex with the ligand of PTA and Imhgroups and further connected into2D structure by hydrogen bonds. Complex （13） is1Dcoordination polymer bridged by pdc2-groups and further connected into2D structure byhydrogen bonds. Complex （14） is3D coordination polymer bridged by btec4-and ox2-groups.â‘¡A series of Fe complexes, Complexes （5）-（8） is Fe（Ⅱ） complexes, in which thecomplexes （5） and （6） are mononuclear structure, bridged to2D,3D infinite supramolecularby different types hydrogen bonds; complex （7） is2D polymer bridged by pdc2-, and futherbridged to3D infinite structure by hydrogen bonds. Complex （8） is1D infinite chain bridgedby the ox2-, and futher bridged to3D network structure by hydrogen bonds.â‘¢A series of Ni complexes, Complexes （15）-（18） are Ni （Ⅱ） mononuclear complexes,further bridged to1D,2D or3D infinite structure by hydrogen bonds.2. The comparative and analysis of SPS and UV–Vis of every series of complexes:â‘ The complexes shows that there are photovoltage responses in the range of300800nm, which reveals they all possess photo–electric conversion properties.The SPS areassociated with the UV–Vis absorption spectra.â‘¡The central metal atoms is different, dnelectronic behavior is also different, so, theSPS is visible difference.â‘¢The center for the same metal complexes:a. The direct coordination atom are different, significantly affect the load transfertransition （LMCT） caused the band to band photovoltaic response number. For example: inthe series of Fe complexes, complex （8） in the direct coordination atom of O atoms,coordination model for FeO6, in the complexes （5）-（7）, direct coordination atom of N and Oatoms, coordination mode respectively, FeN2O4, FeN2O4, FeNO5, observation they werefound by SPS, complex （8） have one photovoltaic response with the band to bandphotovoltaic response; complexes （5）-（7） have two photovoltaic responses with band to bandphotovoltaic response. A series of Co complexes （11）14 also have similar regularity. b. The center metal coordination number is different, the crystal field is different, and thephotoelectric response is also different. Such as: the sixth chapter series Co complexes,complexes （11）-（12） for four-coordinated, in aberrations Td field, d-d*transition absorptionbands of Co（Ⅱ）:4A2→4T1（P）,4A2→4T1（F）,4A2→4T2. Complexes （13）-（14） forsix-coordinated, at the approximate Oh field, d-d*transition absorption bands of Co（Ⅱ）:4T1g（F）→4A2g,4T1g（F）→4T1g（P）,4T1g（F）→4T2g.c. The coordination micro environment is different, for d→d*transition induced by thephotovoltaic response also has significant impact. For example: Co（Ⅱ） is four-coordinated（Tdconfiguration） in （11） and （12）, and the d→d*transition response bands is red-shiftedthan that of （13） and （14）（six-coordinated）, because splittienergy of d orbit in Tdfield （Δt） areless than that in Ohfield （Δo）. |
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