Crystal and molecular structure of N-methylphenazinium bis(maleodinitriledithiolato)nickelate(III), [NMP]⁺ [Ni(mnt)<inf>2</inf>]^-

The crystal and molecular structure of the title compound, C21H11N6S4Ni, is reported. The crystals are triclinic:P-1 (No. 2), Z=4, a=8.768(1), b=11.817(3), c=22.131(3) Å, α=97.44(1), β=91.90(1), and γ=94.04(1)°. The structure was solved by the heavy-atom method, and refined by full-matrix least squares to R=0.039 for 3213 unique reflections. The Ni atoms of both anions in the asymmetric unit have an approximately square-planar configuration. Anions and cations form segregated stacks along a. The stacking of the anions along this direction is dimeric, with alternating Ni-Ni distances 4.111(2) and 7.593(2) Å for molecule I and 4.208(1) and 8.155(2) Å for molecule II. Static susceptibility measurements show strong antiferromagnetic coupling (2J=-241 cm-1) between the two anions of the dimers. © 1985 Plenum Publishing Corporation.