Tetra­aqua­{5-[(pyridin-2-yl­methyl­idene)amino]benzene-1,3-dicarboxyl­ato-κ²N,N′}nickel(II) tetra­hydrate

The title structure, [Ni(C₁₄H₈N₂O₄)(H₂O)₄]·4H₂O, contains a mononuclear Ni^II complex formed by a chelating bidentate Schiff base and by four Ni-bonded water mol­ecules. The Ni^II atom is in a distorted octa­hedral coordination by two N atoms in a cis disposition [Ni—N = 2.0753 (16) and 2.1048 (16) Å] and by four water O atoms [Ni—O = 2.0500 (15)–2.0822 (15) Å]. The crystal structure is completed by four further non-coordinating water mol­ecules and all constituents are linked in a three-dimensional manner by an extensive system of 16 O—H...O hydrogen bonds.