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Abstract: [Ir(η5-C5Me5)(C8H4S8)] (1) [=2-{(4,5-ethylenedithio)-1,3-dithiole-2-ylidene}-1,3-dithiole-4,5-dithionate(2−)] was reacted with iodine in dichloromethane to afford one-electron- and two-electron-oxidized species [IrI(η5-C5Me5)(C8H4S8)] (2), [IrI(η5-C5Me5)(C8H4S8)](I3) (3) and [IrI(η5-C5Me5)(C8H4S8)](I5) (4). The oxidized species exhibit electrical conductivities of (1.1–5.0)×10−6Scm−1 measured for compacted pellets at room temperature. The X-ray crystal structures of the two-electron-oxidized complexes 3 and 4 revealed the Ir–I bonds for both of them and the presence of for 3 and ions for 4 as the counter anions. They have many S–S and S–I non-bonding contacts to form two-dimensional molecular interaction sheets in the solid state. [Copyright &y& Elsevier]

Abstract: [Ir(η5-C5Me5)(C3S5)] [C3S52−=4,5-disulfanyl-1,3-dithiole-2-thionate(2−)] was prepared by a reaction of [NMe4]2[C3S5] with [Ir(η5- C5Me5)Cl2]2 in ethanol. It was reacted with bromine to afford a paramagnetic species [IrBr(η5-C5Me5)(C3S5)] with the Ir–Br bond and in the one-electron-oxidized state, and a diamagnetic dinuclear species [IrBr(η5-C5Me5)(μ-C2S4)IrBr(η5-C5Me5)]. ESR spectra for the one-electron-oxidized species in solution are discussed. The X-ray crystal structural analysis for the latter complex revealed the geometry consisting of dinuclear IrBr(η5-C5Me5) moieties bridged by the C2S42− ligand. [Copyright &y& Elsevier]

[Pt(bpy)(C8H4S8)][BF4] (bpy=2,2′-bipyridine; C8H4S8 2−=2-{(4,5-ethylenedithio)-1,3-dithiole-2-ylidene}-1,3-dithiole-4,5-dithionate(2-)) was prepared by current-controlled electrolysis of a dichloromethane solution of [Pt(bpy)(C8H4S8)] with [NEt4][BF4] as an electrolyte. The X-ray crystal structure analysis revealed a columnar stacking of the one-electron oxidized, cationic moieties with some S–S non-bonded contacts (<3.7 A˚) as well as an S–S layered interaction in another direction. The electrical conductivity measured for a compacted pellet was 5.0×10−3 S cm−1 at room temperature with activation energy of 0.05 eV. The energy band calculation of the oxidized species showed an essentially one-dimensional electron-conduction through the column. [Copyright &y& Elsevier]

Abstract: The preparation, X-ray crystal structures, and magnetic properties of four new rod-shaped hexanuclear Mn clusters [Mn6(O2CCH3)6(EdeaH)2(tmp)2] (1), [Mn6(O2CCH3)6(mdeaH)2(tmp)2] (2), [Mn6(O2CCF3)6(teaH2)2(tmp)2]·2MeCN (3) and [Mn6(O2CPh)6(EdeaH)2(tmp)2]·2Et2O (4), where teaH3 is triethanolamine and tmpH3 is the tris-hydroxymethyl propane ligand, are reported. DC magnetization data along with AC magnetic susceptibility studies show that these complexes have weak antiferromagnetic coupling, appreciable magnetoanisotropy, and ground states of up to S =4. Though all four complexes show a frequency-dependent out-of-phase signal in the AC susceptibility, a characteristic of single-molecule magnets (SMMs), only complexes 1, 2, and 4 are likely to be SMMs with ground states ranging from S =2 to S =4. Complex 3 shows the weakest AC signal and the lowest spin ground state of S ≈1, likely due to small structural differences and intermolecular interactions. [ABSTRACT FROM AUTHOR]