Tetraaquabis(2-oxo-1,2-dihydroquinoline-4-carboxylato-κO 4)nickel(II)

In the title compound, [Ni(C10H6NO3)2(H2O)4], the central NiII atom is located on an inversion center and coordinated in a slightly distorted octahedral geometry by two O atoms from two 2-oxo-1,2-dihydroquinoline-4-carboxylate ligands and four water molecules, all of which act as monodentate ligands. The crystal structure features an extensive network of intermolecular hydrogen-bonding interactions (O—H⋯O and N—H⋯O) and offset face-to-face π–π stacking interactions [centroid–centroid distances = 3.525 (3) and 3.281 (5) Å].