Hydrogen-bonding patterns in 4,4'-bipyridinium bis(3-carboxy-4-hydroxybenzenesulfonate) dihydrate

Studies on hydrogen-bonding. In the title compound, C10H10N22+·2C7H5O6S-·2H2O, 4,4'-bipyridine is centrosymmetric and protonated at both N atoms. The inversion-related hydrogen-bonded supramolecular chains (made up of water molecules and sulfonate motifs arranged in an alternating manner) are cross-linked by 4,4'-bipyridinium cations via N-HO (sulfonate) hydrogen bonds.