ELECTROCHEMICAL STUDY OF CONDUCTING ORGAN IC SALTS GENERATED BY THE OXIDATION OF TETRAMETHYLTETRATHIOFULVALENE IN THE PRESENCE OF NO3- AND I- IONS

The anodic oxidation of TMTTF in the presence of NO3(-) and I- ions ha s been studied in order to detect the formation of mixed-valence salts . Several electrochemical techniques have been used, employing in part icular a carbon-paste electrode. In the case of NO3(-), two solid phas es, TMTTF(NO3)0.05 and TMTTF(NO3)0.50, have been identified from the a nalysis of current/voltage curves measured at a carbon-paste electrode . Bright, black crystals of TMTTF(NO3)0.50 have been isolated by contr olled-potential electrolysis in a 1:1 mixture of acetonitrile and tetr ahydrofuran and the mechanism of formation has been elucidated by line ar sweep voltammetry. In the case of I-, two mixed-valence salts, TMTT FI0.20 and TMTTFI0.50, can exist. These have also been synthetized by controlled-potential electrolysis in a mixture of acetonitrile- tetrah ydrofuran (9:1). The electrical conductivity of TMTTFI0.02 has been in vestigated.