X-Ray crystal structure of tetra-acetatobis(tetrathiafulvalene)dirhodium(II) and the properties of its iodine-doped complex

Abstract

A single-crystal X-ray structure analysis of [Rh₂(O₂CCH₃)₄(ttf)₂](ttf = tetrathiafulvalene) revealed a tetra-acetatodirhodium(II) framework co-ordinated by two ttf molecules each through a sulphur atom. The essentially neutral ttf molecule assumes a boat conformation in which the four terminal carbon atoms deviate greatly from the central C₂S₄ plane. In the crystal phase the ttf molecules weakly interact with one another to form a two-dimensional network through sulphur–sulphur contacts. The complex crystallizes in the monoclinic system, space group P2₁/n with unit-cell dimensions a= 12.496(3), b= 14.413(3), c= 8.296(2)Å, β= 104.27(2)°, and Z= 2. The structure was solved by a standard heavy-atom method and refined, on the basis of 1 734 [|F_o| > 3σ(F)] observed data, to an R value of 0.082. The complex was doped with iodine to afford [Rh₂(O₂CCH₃)₄(ttf)₂]·l₃ which contains neutral ttf and the ttf˙⁺ radical cation and exhibits a conductivity of 2.0 × 10^–7 S cm^–1 at 25 °C for a compacted pellet.