Bis[μ-N,N'-bis(salicylidene)-1,3-propanediaminato]bis(dimethylformamide)di(μ-nitrito)copper(II)dinickel(II)–Dimethylformamide (1/2)

The unit cell of the title compound, [CuNi₂(NO₂)₂(C₁₇H₁₆N₂O₂)₂(C₃H₇NO)₂].2C₃H₇NO, contains two molecules of the linear heterotrinuclear complex and four solvent molecules. The central Cu^II ion and the terminal Ni^II ions have distorted octahedral coordination spheres. The Cu–Ni pairs are each triply bridged, by the O atoms of an N,N'-bis(salicylidene)-1,3-propanediaminato (salpd²⁻) ligand and by an O and an N atom of a nitrite group. The central Cu^II ion, located on an inversion centre, has a total of six O atoms in its coordination sphere: two from each salpd²⁻ ligand and one from each bridging nitrite group. The Ni^II ions are related by the inversion centre and each is coordinated by the two O and two N atoms of a salpd²⁻ ligand and one N atom from a nitrite and an O atom from a dimethylformamide (dmf) ligand. The dmf and nitrite groups are mutually trans about the Ni^II ion. The Cu—Ni distance is 2.9967 (4) Å.

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