Crystal Structure Of Bis(Ethylenedithio)Tetrathiafulvalenium Mu(2)-Acetato-Bis[Tribromidorhenate(Iii)] 1,1,2-Trichloroethane Hemisolvate

The asymmetric unit of the title salt, (C10H8S8)[Re2Br6(CH3COO)]center dot 0.5C(2)H(3)Cl(3), contains one bis(ethylenedithio)tetrathiafulvalene (ET) radical cation, one mu(2)-acetato-bis[tribromidorhenate(III)] anion and a 1,1,2-trichloroethane molecule with half-occupancy disordered about a twofold rotation axis. The tetrathiafulvalene fragment adopts an almost planar configuration typical of the ET radical cation. The C atoms of both ethylenedithio fragments in the cation are disordered over two orientations with occupancy factors 0.65:0.35 and 0.77:0.23. In the anion, six Br atoms and a mu(2)-acetate ligand form a strongly distorted cubic O2Br6 coordination polyhedron around the Re-2 dinuclear centre. In the crystal, centrosymmetrically related ET cations and Re2O2Br6 anions are linked into dimers by pi-pi stacking interactions [centroid-to-centroid distance = 3.826 (8) angstrom] and by pairs of additional Re center dot center dot center dot Br contacts [3.131 (3) angstrom], respectively. The dimers are further packed into a three-dimensional network by non-directional interionic electrostatic forces and by C-H center dot center dot center dot Br and C-H center dot center dot center dot S hydrogen bonds. The disordered 1,1,2-trichloroethane molecules occupy solvent-accessible channels along the b axis.