Crystal structure of 8-hydroxyquinolinium 2-carboxy-6-nitrobenzoate monohydrate

In the title hydrated salt, C9H8NO+·C8H4NO6−·H2O, the deprotonated carboxylate group is almost normal to its attached benzene ring [dihedral angle = 83.56 (8)°], whereas the protonated carboxylate group is close to parallel [dihedral angle = 24.56 (9)°]. In the crystal, the components are linked by N—H...O and O—H...O hydrogen bonds, generating [001] chains. The packing is consolidated by C—H...O and π–π [centroid-to-centroid distances = 3.6408 (9) and 3.6507 (9) Å] interactions, which result in a three-dimensional network.