Di-μ-sulfato-bis-[diaqua-(1H-imidazo[4,5-f][1,10]phenanthroline)nickel(II)] dihydrate.

In the title compound, [Ni2(SO4)2(C13H8N4)2(H2O)4]·2H2O, the complete dimeric complex is generated by an inversion center. The NiII atoms are octa­hedrally coordinated by two N atoms from one 1H-imidazo[4,5-f][1,10]phenanthroline (IP) ligand and two O atoms from two adjacent sulfate ions forming the equatorial plane, with two coordinated water mol­ecules in the axial sites. Both of the sulfate ions act as bidentate-bridging ligands connecting the two NiII ions, thus generating a binuclear complex. In the crystal structure, O—H⋯O and O—H⋯N hydrogen bonds involving the coordinated and uncoordinated water mol­ecules and N—H⋯O links lead to the formation of a two-dimensional sheet structure developing parallel to (010). Weak π–π stacking inter­actions [centroid–centroid separation = 3.613 (2) A] between the IP ligands also occur.