Tetrathiafulvalene S-oxide: a potential ‘donor impurity’ in the organic metal TTF–TCNQ

Abstract

Tetrathiafulvalene S-oxide, which because of its size similarity with tetrathiafulvalene is a potential ‘donor impurity’ in the organic metal TTF–TCNQ, was prepared and characterized spectroscopically. Experiments in which tetrathiafulvalene S-oxide was purposely doped into TTF–TCNQ indicate, however, that the S-oxide is not of major importance for the electrical conductivity of the TTF–TCNQ crystals. The surface of TTF–TCNQ crystals, which had been exposed to air, was analysed by means of ESCA spectroscopy. The results strongly indicate the presence of a totally oxidized surface