Intermolecular interactions and charge transfer in the 2:1 tetrathiafulvalene bromanil complex, (TTF) 2 ‐BA

The crystal structure of the 2:1 charge‐transfer complex of tetrathiafulvalene [2,2′‐bis(1,3‐dithiolylidene)] and bromanil (tetrabromo‐1,4‐benzoquinone) [(TTF) 2 ‐BA, (C 6 H 4 S 4 ) 2 –C 6 Br 4 O 2 ] has been determined by X‐ray diffraction at room temperature, 100 and 25 K. No structural phase transition occurs in the temperature range studied. The crystal is made of TTF–BA–TTF sandwich trimers. A charge‐transfer estimation between donor and acceptor (0.2 e) molecules is proposed in comparison to the molecular geometries of TTF–BA and TTF and BA isolated molecules. Displacement parameters of the molecules have been modeled with the TLS formalism.