ASSEMBLY OF PARTIALLY OXIDIZED TETRATHIAFULVALENE IN LAYERED PHOSPHATES - FORMATION OF CONDUCTING ORGANIC-INORGANIC HYBRIDS BY INTERCALATION

Intercalation and ion-exchange reactions have been used for the synthe sis of novel inorganic-organic hybrid materials comprised of tetrathia fulvalene (TTF) conducting chains interleaved with insulating zirconiu m phosphate layers. Two different synthetic strategies are described. in the first approach, we have attempted the oxidative insertion of ne utral TTF into a Zr(PO4)(HPO4)(2) . 2H(2)O host preexchanged with CU2. In tile second method, surfactant or long-chain alcohols have been u sed to expand the layers of the host structure, allowing the intercala tion of partially charged TTF molecules. This latter approach produced materials with metal-like conductivity that exceeds by a factor of 10 (7) that of the precursors. These compounds have been characterized by vibrational, UV-vis, acid EPR spectroscopies, and transport propertie s (conductivity and thermoelectrical power) have been measured as a fu nction of the temperature from -150 to 50 degrees C. The properties ob served show marked similarity with those displayed by mixed valence TT F halides and pseudohalides, The reactions occur topotactically, and t he increase in interlayer distance is compatible with an orientation o f TTF perpendicular, or nearly, to the host layers.