LANGMUIR-BLODGETT-FILMS OF A TETRATHIAFULVALENE DERIVATIVE SUBSTITUTED WITH AN AZOBENZENE GROUP

The new tetrathiafulvalene derivative 1, functionalised with an azoben zene substituent, has been synthesised. Cyclic voltammetric and spectr oelectrochemical studies in solution demonstrate the reversible format ion of the radical cation of 1. UV-VIS spectroscopy suggests that ther e is a weak interaction between the TTF and azobenzene moieties in com pound 1, and demonstrates that trans-cis isomerisation occurs upon pho tolysis of the azobenzene substituent. Semi-conducting LB films of 1 h ave been assembled without the need for added fatty acid: room tempera ture conductivity values of the films before and after doping with iod ine vapour were sigma(rt) = 10(-3)-10(-5) S cm(-1) and 2 x 10(-2)-10(- 3) S cm(-1), respectively. No change in the conductivity of the LB fil ms was observed under irradiation.