Structure of the Chromium(III) Salt [Cp^*₂Cr]⁺[Cp^*CrCl₃]⁻

The title compound, bis­(η⁵-pentamethylcyclopentadienyl)chromium(III) trichloro­(η⁵-pentamethylcyclopentadienyl)chromium(III), [Cr(C₁₀H₁₅)₂][CrCl₃(C₁₀H₁₅)], is a salt consisting of discrete anionic [{η⁵-C₅(CH₃)₅}CrCl₃]⁻ and cationic [{η⁵.C₅(CH₃)₅}₂Cr]⁺ chromium(III) species. The anion adopts a `three-legged piano stool' structure whereas the cation displays a staggered orientation of the C₅ rings and approximates to D_5 d local symmetry. Cr—C distances range from 2.177 (5) to 2.208 (4) Å in the cation and from 2.234 (4) to 2.265 (5) Å in the anion; Cr—Cl distances in the anion fall in the range 2.320 (1)–2.331 (1) Å.

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