Bis(imidazolium) diaqua­bis(pyridine-2,5-dicarboxyl­ato-κ²N,O)cobaltate(II) tetra­hydrate

The title complex, (C₃H₅N₂)₂[Co(C₇H₃NO₄)₂(H₂O)₂]·4H₂O, was prepared by a hydro­thermal reaction. Each Co^II atom is located on a crystallographic inversion centre and displays a distorted octa­hedral coordination geometry. The face-to-face distance of 3.529 (7) Å between partially overlapped parallel pyridine rings reflects a π–π stacking inter­action between neighbouring Co^II complex mol­ecules. A network of O—H...O and O—H...N hydrogen bonds helps to stabilize the crystal packing.