Crystal structure and surface photo-electric property of Mn(II) coordination supramolecules

Abstract

Two Mn(II) coordination supramolecules, [Mn2(C8H7O2)4(phen)2(μ-H2O)] (1) and [Mn2(btec)(phen)2(H2O)6]·2H2O (2) (phen=1,10-phenanthroline, H4btec=1,2,4,5-benzenetetracarboxylic acid), were synthesized by hydrothermal method. The crystal structures of the complexes were determined by X-ray single crystal diffraction. The result indicates that (1) and (2) are both binuclear Mn(II) complexes. The existence of hydrogen bonds makes the binuclear complexes become further connected to coordination supramolecules, which possess 1D and 3D infinite structures respectively. The complexes were identified by IR, UV-Vis, surface photovoltage spectrum (SPS) and field-induced surface photovoltage spectrum (FISPS). The results of SPS for the complexes indicate that they both exhibit positive surface photovoltage response bands in the range of 300–600 nm. The SPS phase spectrum and FISPS of complexes indicate that they show certain p-type semiconductor characteristic. However, the intensity, position and number of the SPV response bands are different obviously. The difference of the SPV response bands is mainly attributed to the different structures of the complexes and the different coordination environment of Mn(II) in the two complexes. This paper discusses the action of hydrogen bonds in the construction of the supramolecule and the change on the surface photovoltage of complex in different coordination environment.