Bis(8-hydroxy-1-methylquinolin-1-ium) bis(1,2-dicyanoethene-1,2-dithiolato)nickelate(II) dihydrate

In the title ion-pair complex, (C10H10NO)2[Ni(C4N2S2)2]·2H2O, the anion has crystallographically imposed centre of symmetry. The NiII atom exhibits a slightly distorted square-planar coordination geometry. In the crystal, the water molecule links anions and cations into a three-dimensional network via O—H...N, O—H...S and O—H...O hydrogen bonds. The structure is further stabilized by weak S...π contacts [S...centroid = 3.8047 (9) Å] and π–π stacking interactions [centriod–centroid distance = 3.8653 (7) Å].