Identification of the cobalt(II) chloride 'mixed' solvate Co4Cl8(H2O)4(MeCN)6: the ionic structure trans-[Co(H2O)2(MeCN)4] trans-[Co(H2O)2(MeCN)2(CoCl4)2]

The structure of the title compound features mononuclear octahedral Co^sup II^ cations, trans-[Co(H^sub 2^O)^sub 2^(MeCN)^sub 4^]^sup 2+^, and trinuclear anions, trans-[Co(H^sub 2^O)^sub 2^(MeCN)^sub 2^(CoCl^sub 4^)^sub 2^]^sup 2-^; the latter centrosymmetric units contain a central octahedral Co(H^sub 2^O)^sub 2^(MeCN)^sub 2^ moiety with two tetrahedral [CoCl^sub 4^]^sup 2-^ ligands. These two large ions are held in a network of intra- and inter-molecular hydrogen bonding.[PUBLICATION ABSTRACT]