Hydrogen bonding and C-H•••O interactions in bis(4-carboxyquinolinium) sulfate monohydrate

The title substance, 2C(10)H(8)NO(2)(+)-SO42-. H2O, crystallized in the centrosymmetric space group P (1) over bar with two organic cations, one sulfate ion and one water molecule in the asymmetric unit. Seven leading intermolecular hydrogen bonds are formed in this structure: two N-H ... O bonds have N ... O distances of 2.592(3) and 2.650 (3) Angstrom, while five O-H ... O bonds have O ... O distances ranging from 2.493(2) to 3.072(3) Angstrom. All of the potential donors are involved in these bonds, but three of the potential nine acceptors are not. The H and O atoms in all these hydrogen bonds are ordered. The hydrogen bonds form a three-dimensional network. In addition, there are nine significant C-H ... O interactions for which the H ... O distances are less than the corresponding van der Waals radii sum. The dihedral angle between the best-fit quinoline core plane and the carboxyl group plane is 35.2(3)degrees for one of the organic cations and 6.4(4)degrees for the other.