Bis(2,6-diamino-pyridinium) bis-(pyridine-2,6-dicarboxyl-ato)zincate(II) monohydrate.

In the title hydrated mol-ecular salt, (C(5)H(8)N(3))(2)[Zn(C(7)H(3)NO(4))(2)]·H(2)O, the Zn(II) atom is coordinated by two O,N,O'-tridentate pyridine-2,6-dicarboxyl-ate dianions, generating a slightly distorted trans-ZnN(2)O(4) octa-hedral coordination geometry for the metal ion. In the crystal, a network of O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds involving the cations, anions and water mol-ecules results in a three-dimensional network.