Bis[bis-(penta-methyl-cyclo-penta-dien-yl)cobalt(III)] tetra-chlorido-cobaltate(II) di-chloro-methane disolvate.

The title compound, [Co(C10H15)2]2[CoCl4]·2CH2Cl2, was isolated as a dichloromethane solvate and was formed in the reaction between lithium penta-methyl-cyclo-penta-dienide and anyhydrous cobalt(II) chloride in tetra-hydro-furan. There are two deca-methyl-cobaltocenium cations, one tetrachloridocobaltate(II) anion and two di-chloro-methane solvent mol-ecules in the formula unit. There is a slight disorder of the di-chloro-methane solvent which was treated with a two-site model [occupancy rates = 0.765 (4) and 0.235 (4)]. The di-chloro-methane mol-ecules display significant C-H⋯Cl inter-actions with the tetrachloridocobaltate(II) dianion. The cobalt atom of the deca-methyl-cobaltocenium cation sits on a twofold rotation axis, with only one penta-methyl-cyclo-penta-diene ligand being unique and the second generated by symmetry. The cobalt atom of the [CoCl4](-2) ion sits on a special site with -4 symmetry, with one unique chloride ligand and the others generated by the fourfold inversion axis.