Radical Cation Salts of Tetramethyltetrathiafulvalene (TM-TTF) and Tetramethyltetraselenafulvalene (TM-TSF) with Chlorocyananilate-Based Anions

Electrocrystallization of tetramethyltetrathiafulvalene (TM-TTF) and tetramethyltetraselenafulvalene (TM-TSF) with chlorocyananilate monoanion or/and tris­(chlorocyananilato)­ferrate­(III) in THF/DCM solvent mixtures yielded a salt formulated as [TM-TTF]₄[K­(HClCNAn)₄] (1) with the former and π–d hybrid systems, formulated as [TM-TTF]₅[Fe­(ClCNAn)₃]·2CH₂Cl₂ (2) and [TM-TSF]₃[Fe­(ClCNAn)₃]·0.5CH₂Cl·2.5H₂O (3), respectively, with the latter. Compound 1 shows segregation of TM-TTF donor molecules and K­(HClCNAn)₄ anionic clusters in the bc plane. The donor molecules are present as mixed-valence dimers and show a β′ packing arrangement. Compounds 2 and 3 consist of hybrid organic/inorganic structures with no segregation of [Fe­(ClCNAn)₃]^3– anionic complexes and organic TM-TTF/TM-TSF donors. In the structure of compound 3, TM-TSF dimers are trapped between anilate units of metal complexes of opposite chirality. Furthermore, tetrameric donor motifs and solvent molecules of crystallization complete the structure. Single-crystal conductivity measurements on compounds 1 and 2 show semiconducting behavior with room-temperature conductivity values of 5 × 10^–5 and 2 × 10^–4 10 S cm^–1 and activation energies of 1960 and 1900 K, respectively. Under high pressure, compound 2 remains a semiconductor, yet its room-temperature conductivity value strongly increases up to 0.2 S cm^–1 at 9.8 GPa.