A novel gadolinium tetra(4-sulfonatophenyl)porphyrin-amino acid complex with interesting photophysical and electrochemical properties

摘要

A solvothermal reaction of GdCl3 center dot 6H(2)O, H6TPPS, and histidine led to the formation of a novel gadolinium tetra(4-sulfonatophenyl) porphyrin-amino acid hybrid, namely, {[Gd(His)(H2O)][Gd(H3O)(3)](H2TPPS)(2)}(n)center dot 3nH(2)O (1) [His = histidine; H6TPPS = tetra(4-sulfonatophenyl) porphyrin]. The molecular structure of complex 1, which was determined by single-crystal X-ray diffraction technique, shows that the porphyrin macrocycle is saddle-distorted and its center is non-metalated. The gadolinium ions show two kinds of coordination geometry, i.e., a distorted nine-coordinated monocapped square antiprism and a contorted square antiprism. Complex 1 features a three-dimensional structure which is constructed from the gadolinium ions connecting the porphyrin moieties together. The photoluminescence study reveals that it displays an emission in the red region. The cyclic voltammetry/differential pulse voltammetry, FT-IR, and UV-Vis of complex 1 were also investigated in detail.