[Synthesis and spectroscopy of Dawson molybdovanadophosphoric acid charge-transfer complexes]
Li-hua Gao1, Ke-zhi Wang, Xiu-lan Xin
1Department of Chemistry, Beijing Normal University, Beijing 100875, China.
Abstract:
A series of organic-inorganic charge-transfer complexes formed by (E)-N-butyl-4-(2-(4-dimethylaminophenyl)ethenyl)pyridinium bromide with Dawson molybdovanadophosphorate have been synthesized and characterized by elemental analyses, thermogravimetric analyses, UV-Vis, IR and X ray photoelectron spectroscopy. IR spectrum confirms the presence of the same type of stacks and presence of the hemicyanine cation and the molybdovanadophosphorate anion in the title complexes. The results show that 6:1 supramolecular complexes are formed between the hemicyanine cations and the heteropoly anions, and the charge transfer occurs from the hemicyanine cations to the heteropoly anions. The interaction between the hemicyanine cations and the heteropoly anions in the solid powder is stronger than in the fluid solution. The compounds reported in this paper are interesting as catalysts and nonlinear optical materials.
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