Bis(9-amino­acridinium) bis­(pyridine-2,6-dicarboxyl­ato)zincate(II) trihydrate

In the title compound, (C(13)H(11)N(2))(2)[Zn(C(7)H(3)NO(4))(2)]·3H(2)O, the Zn(II) ion is six-coordinated with the N(4)O(2) donor set being a distorted octa­hedron through two almost perpendicular (r.m.s. deviation of ligand atoms from the mean plane is 0.057 Å) tridentate pyridine-2,6-dicarboxyl­ate ligands [dihedral angle between the ligands = 86.06 (4)°]. The charge is compensated by two 9-amino­acridinium cations protonated on the ring N atom. A variety of inter­molecular contacts, such as ion–ion, N—H⋯O and O—H⋯O hydrogen bonds, and π–π stacking [centroid–centroid distances = 3.4907 (9)–4.1128 (8) Å], between cations and between anions, play important roles in the formation of the three-dimensional network.