A linear trinuclear NiII-MnII-NiII complex with a μ-acetato bridge:: Bis{(μ-acetato)[μ-bis(salicylidene)-1,3-propanediaminato] (N,N-dimethylformamide)nickel(II)}manganese(II)

The structure of the title compound, [Mn{Ni(C2H3O2)(C3H7NO)(C17H16N2O2)}(2)], consists Of a linear heterotrinuclear unit with a central Mn-II ion. Both the terminal Ni-II ions and the central Mn-II ion have irregular octahedral coordinations. The central Mn-II ion is located on the inversion centre. Each pair of metal ions is triply bridged via O atoms from the N,N'-bis(salicylidene)-1,3-propanediaminato (SALPD(2-)) ligands and from the acetate groups. The coordination around the Mn-II ion consists of four O atoms from two SALPD(2-) ligands, and one O atom from each of two acetate ligands. The coordination of each terminal Ni-II ion is provided by the two O and two N atoms from a SALPD(2-) ligand, and by one O atom each from a bridging acetate and a dimethylformamide (dmf) ligand. The dmf and acetate ligands are trans about the terminal Ni-II ion. The average Ni-O and Ni-N distances for the terminal ions are 2.071(2) and 2.026 (2)Angstrom, respectively. The Ni ... Mn distance is 3.133 (2) Angstrom.