Crystal structure of bis­[1-(naphthalen-1-ylmeth­yl)pyridinium] bis­(2,2-di­cyano­ethene-1,1-di­thiol­ato-κ(2) S,S′)nickelate(II)

A new ion-pair complex, (C(16)H(14)N)(2)[Ni(C(4)N(2)S(2))(2)] or (1-NaMePy)(2)[Ni(imnt)(2)], where 1-NaMePy is 1-(4-naphthyl­methyl­ene)pyridinium and imnt is 2,2-di­cyano­ethene-1,1-di­thiol­ate, was obtained by the direct reaction of NiCl(2), K(2)imnt and (1-NaMePy)(+)Br(−) in H(2)O. The asymmetric unit contains a [1-NaMePy](+) cation and one half of an Ni(imnt)(2) (2−) anion. The Ni(II) ion lies on an inversion centre and adopts a square-planar configuration with Ni—S bond lengths of 2.200 (1) and 2.216 (1) Å. In the [1-NaMePy](+) cation, the naphthyl ringsystem and the pyridinium ring make a dihedral angle of 90.0 (2)°. In the crystal, C—H⋯N and C—H⋯Ni hydrogen bonds, as well as π–π inter­actions between the chelate ring and the pyridinium ring [centroid–centroid distance = 3.675 (2) Å] link the ions into a three-dimensional network.