Triaqua­dichlorido[5-(4-pyridinio)tetra­zolato-κN (2)]cobalt(II) monohydrate

The title compound, [CoCl(2)(C(6)H(5)N(5))(H(2)O)(3)]·H(2)O, was synthesized by hydro­thermal reaction of CoCl(2) with 4-(2H-tetra­zol-5-yl)pyridine. The Co(II) cation is coordinated by two Cl(−) ions, one N atom from the 5-(4-pyridinio)tetra­zolate zwitterion and three O atoms from three water mol­ecules in a distorted octa­hedral geometry. In the crystal, mol­ecules are linked into a three-dimensional network by N—H⋯Cl hydrogen bonds and O—H⋯O/N/Cl hydrogen bonds involv­ing both coordinated and uncoordinated water mol­ecules. Strong π–π stacking is present between parallel pyridinium and tetra­zolate rings [centroid–centroid distances = 3.411 (2) and 3.436 (2) Å].