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The asymmetric unit of the title salt, (C10H8S8)[Re2Br6(CH3COO)]·0.5C2H3Cl3, contains one bis(ethylenedithio)tetrathiafulvalene (ET) radical cation, one μ2-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 μ2-acetate ligand form a strongly distorted cubic O2Br6 coordination polyhedron around the Re2 dinuclear centre. In the crystal, centrosymmetrically related ET cations and Re2O2Br6 anions are linked into dimers by π–π stacking interactions [centroid-to-centroid distance = 3.826 (8) Å] and by pairs of additional Re...Br contacts [3.131 (3) Å], respectively. The dimers are further packed into a three-dimensional network by non-directional interionic electrostatic forces and by C—H...Br and C—H...S hydrogen bonds. The disordered 1,1,2-trichloroethane molecules occupy solvent-accessible channels along the b axis.

Abstract: The synthesis and the redox behaviour of electroactive donor molecules incorporating an azino spacer group between a benzoselenazole core and another heterocyclic moiety, either a benzoselenazole one or a thiazole one, are reported. Neutral complexes were obtained with TCNQ and, for the first time with dithiadiazafulvalene or diselenadiazafulvalene derivatives, cation radical salts by electrocrystallization. Crystal structures data of these complexes are presented and their geometries compared with those deduced from theoretical calculations. [Copyright &y& Elsevier]

Abstract: The first polymorph, κ″-(ET)2Cu[N(CN)2]Cl, of the well known Mott insulator κ-(ET)2Cu[N(CN)2]Cl has been prepared and its crystal and electronic structures have been examined. The polymorph has monoclinic symmetry in contrast with the orthorhombic one of the isostructural κ-salts of the family (ET)2Cu[N(CN)2]X (X=Cl, Br, I). The monoclinic phase exhibits a layered structure in which the conducting layers are packed in a κ-type arrangement and the anion sheets consist of polymeric zigzag chains formed by Cu[N(CN)2]Cl units. The main structural differences with the orthorhombic κ-salts are that the anion sheets are disordered and the ET molecules are less planar. The new polymorph shows metallic type resistivity down to 4.2K. [Copyright &y& Elsevier]

Abstract: The synthesis of the protected TTF tetrathiolate 2,3,6,7-tetrakis(2-cyanoethylthio)tetrathiafulvalene (TCE-TTF), as well as those of five new radical cation salts [TCE-TTF](X), X− =PF6 −, CF3SO3 −, BF4 −, obtained by electrocrystallization technique is presented. Five crystal structures of these materials based on their fully oxidized donor molecules are described. The flexibility of the cyanoethylene arm yields two conformations cis and trans to the molecule. Then compounds with PF6 − and BF4 − anions crystallized as two different phases. All these materials are insulators, and the magnetic studies of one phase of [TCE-TTF](PF6) revealed an antiferromagnetic behavior. [Copyright &y& Elsevier]

Seven conductive radical cation salts based on MDSe-TSF (methylenediselenotetraselenafulvalene) have been synthesized by electrocrystallization in the presence of Cl−, Br−, I3−, I2Br−, PF6−, ClO4−, and Cu(NCS)2− counter anions. The crystal appearances of these salts fairly depend on the anions employed. X-ray crystallographic analyses have revealed that the PF6 and ClO4 salts in the shape of brown thin plates adopt the θ-type structures characterized by the herringbone arrangement of donor stacks, whereas the Cl and Br salts in the shape of black thick plates favor the κ-type structures with the orthogonal arrangement of donor dimers. Regardless of different crystal appearances or crystal packing patterns, all these salts show high conductivity (>102 S cm−1) at room temperature and retain metallic properties down to 4.2 K. Of them, the Br salt shows a weak but distinct diamagnetic shielding signal below 4 K in the dc magnetization measurement under zero-field-cooled (ZFC) condition, suggesting a sign of superconductivity. The band calculations of both PF6 and Br salts demonstrate closed Fermi surfaces indicative of two-dimensional molecular conductors. [Copyright &y& Elsevier]