Charge transfer salts based on Cu(qdt)2, Ni(qdt)2 and Au(qdt)2 anions

Metal bis(quinoxaline-2,3-dithiolate) complexes, M(qdt)2, were used as counterions of radical-cation salts commonly employed in the preparation of one-dimensional conductors. We report the synthesis of the new complex Au(qdt)2−as the tetraphenylphosphonium salt and the preparation of (bedt-ttf)M(qdt)2, (tmtsf) M(qdt)2 and (ttf)M(qdt)2 with M=Au and Cu, and (ttf)3[Ni(qdt)2]2. Their electrical conductivity and thermoelectric power were measured showing in all cases activated behaviour, with room temperature values of σ ranging from 10−7 to 10−3 S cm−1, the highest value being for (bedt-ttf)Au(qdt)2 which has a gap 2Δ=0.32 eV. Preliminary E.S.R. results for (ttf)Cu(qdt)2 are also presented.