Crystal structure of 4,4′-bipyridine-1,1'-diium naphthalene-2,6-disulfonate dihydrate

Abstract

The title hydrated molecular organic salt, C10H10N22+·C10H6O6S22−·2H2O, crystallized with half a bipyridinium cation, half a naphthalene-2,6-disulfonate anion and a water molecule in the asymmetric unit. The whole cation and anion are generated by inversion symmetry, the inversion centers being at the center of the bridging C—C bond of the cation, and at the center of the fused C—C bond of the naphthalene group of the anion. In the crystal, the anions and cations stack alternately along theaaxis with π–π interactions [inter-centroid distance = 3.491 (1) Å]. The anions are linkedviaO—H...O(sulfonate) hydrogen bonds involving two inversion-related water molecules, forming chains along [10-1]. These chains are bridged by bifurcated N—H...(O,O) hydrogen bonds, forming a three-dimensional framework structure. There are also C—H...O hydrogen bonds present, reinforcing the framework structure.