Synthesis, Crystal Structure, and Spectral Characterization of Novel Three-dimensional Supramolecular Networks with One-dimensional Channels Based on Keggin-type Polyoxoanions and Mixed-Valence Dibenzotetrathiafulvalenes
A new organic/inorganic salt formed by mixed-valence dibenzotetrathiafulvalene (DBTTF) radical cations and the spherical Keggin-type polyoxometalate anions [H3BW12O40]2− was obtained by electrochemical oxidation of the donor in an acetonitrile and a 1,2-dichloroethane solution containing the polyanion. The compound has been characterized by X-ray diffraction, elemental analysis, EPR, IR and Raman spectroscopy. X-Ray diffraction experiments have revealed that the compound consists of heteropolyanions, water molecules and DBTTF radical cations. The organic radicals form trimers and dimers via π-π stacking; moreover, the polyoxoanions and the organic donors are also held together by hydrogen bonding interactions. In their packing arrangement, a three-dimensional supramolecular network with one-dimensional channels along the b axis is established with uncoordinated water molecules residing in the channels.