Synthesis, Structure And Surface Photoelectric Property Of A Series Of Cu~?/Cu~?and Fe~?/Fe~? Complexes

Nine complexes of Cu^?/Cu^?and Fe^?/Fe^?with N-heterocyclic ligand have been synthesized by the hydrothermal methods.All single crystals were obtained and determined by X-ray single crystal diffraction.And they were characterized by infrared spectra?IR?,UV-Vis absorption spectra?UV-Vis?and surface photovoltage spectroscopy?SPS?.The surface photoelectric properties of complexes are studied especially.The formulas of nine complexes are listed as follows:?1?[Cu?dpa???-Cl?Cd?aip?]·H₂O?2?[Cu?2,6-pdc??pz??H₂O?·2H₂O]?3?[Cu?2-pzc?₂?H₂O?₂]?4?[Cu?Imbc?₂?H₂O?₂]?5?[Cu?phen??H₂O?₂SO₄]_n?6?[Cu?2,2-bipy??H₂O?₂SO₄]_n?7?[Cu₂?ClC₆H₄COO?₄?C₂H₅OH?₂]?8?[Fe₃?CN?₄?dpa?₄?O₂?]_n?9?[Fe₂?CN?₂?dpa??O₂?]_n?10?{[Fe?phen?₃][Fe?CN?₆]·0.5phen·5H₂O}?dpa=Bis?4-pyridyl?amine,aip=5-Aminoisophthalic acid,2,6-pdc=2,6-Pyridinedicar-boxylic acid,2-pzc=2-Pyrazinecarboxylic acid,Imbc=4,5-Imidazole dicarboxylic acid,2,2'-bipy=2,2-Dipyridyl,phen=1,10-Phenanthroline monohydrate,ClC₆H₄COOH=4-Chl orobenzoicacid?The structural analyses indicate that:[1]The complexes?1?-?7?are Cu?I?or Cu?II?coordination complexes.Complex?1?is a 1D Cu^I-Cd^II heteronuclear coordination polymers,complexes?2?-?6?are Cu?II?coordination supramolecules,complex?7?is a binuclear Cu?II?molecular complex.Therein,complexes?3?-?5?are bridged to 2D,3D,2D supramolecule by hydrogen bonds,respectively.[2]Complexes?8?and?9?are novel Fe?II?coordination polymers which are not documented,in which Fe?II?ions are bridged by CN^-and O₂^2-and finally linked into a peculiar 3D network.In the crystal of both complexes,there is a hexagonal ring with chair conformation formed by six Fe?II?,two CN^-and two O₂^2-.The stucture difference between two complexes?8?and?9?is that the pillar sustains 2D layers is different.In complex?8?,the[Fe?CN?₂]unit acts as the pillar.The[Fe₂?CN?₂?O₂?]unit is pillar in complex?9?.This leads in the difference of separation between layers,that of complex?8?is 9.554?and complex?9?is 13.855?.Complex?10?is a Fe?III?ion complex.The surface photovoltage properties of all complexes are investigated using surface photovoltage technology.In SPS analyses,the complexes are regarded as a semiconductor,using the semiconductor energy theory and crystal field theory of complex,the SPS of nine complexes are analysized,discussed and associated with UV-Vis spectra,the results are listed as following:[1]The nine complexes exhibit obvious photovoltage responses in the range of 300⁸00nm under the inducement of UV-Vis light,which indicates that they all possess certain photo-electric conversion properties.[2]There presents good corresponding relationship between SPS and UV-Vis absorption spectra.[3]The structural dimension of complexes affects the intensity of the SPS response band.The dimension is higher,the intensity of response band is stronger.For example,in complexes?4?-?6?,complexes?4?and?5?are bridged into 3D and 2D supramolecule by hydrogen bonds,complex?6?is a 1D structure.The existence of a network of hydrogen bonds,which may provide more transitional ways for electrons and holes thus the SPS intensity is?4?>?5?>?6?.[4]The valence and crystal field strength of center metal affect the number and width of SPS response.For example,in complexes?8?-?10?,complexes?8?and?9?are Fe?II?complex with similar structure,and Fe?II?ion is four-coordinate with tetrahedral geometry.In SPS,there is a d?d*transition response bands.Comlpex?10?is Fe?III?complex with six-coordinate lying in octehedral geometry,there are two d?d*transition response bands in SPS.In addition,the conjugation property of ligand affects the width of the SPS response band.In complex?10?,the introduction of phen with good conjugation structure makes the scope of response band caused by LMCT transition wider than that of complexes?8?and?9?.