The co-crystal N,N′-bis­[(pyridin-1-ium-2-yl)meth­yl]ethane­dithio­amide bis­(2,6-di­nitro­benzoate)–2,6-di­nitro­benzoic acid (1/4)

The asymmetric unit of title co-crystal, C₁₄H₁₆N₄S₂²⁺·2C₇H₃N₂O₆⁻·4C₇H₄N₂O₆, comprises a centrosymmetric dipyridinium dication, a 2,6-di­nitro­benzoate anion and two independent 2,6-di­nitro­benzoic acid mol­ecules. The pyridin­ium rings are each approximately perpendicular to the central di­thio­amide unit [dihedral angle = 80.67 (12)°]. The carboxyl­ate/carb­oxy­lic acid groups are approximately perpendicular to the benzene ring to which they are attached [dihedral angles = 78.85 (16), 81.46 (19) and 71.28 (15)°]. By contrast, the major twist exhibited by a nitro group is manifested in a dihedral angle of 32.66 (17)°. The most prominent feature of the crystal packing is linear supra­molecular chains along [1-10], featuring O—H...O(carboxyl­ate) and pyridinium-N—H...O hydrogen bonds. These are consolidated into a three-dimensional architecture by thio­amide–nitro N—H...O, C—H...O and π–π [inter-centroid distance = 3.524 (2) Å] inter­actions. One of the nitro O atoms was refined over two sites; the major site was 0.65 (7) occupied.

4-[2-(Pyridin-1-ium-4-yl)eth­yl]pyridin-1-ium bis­(2,6-di­nitro­benzoate)

The asymmetric unit of the title salt, C₁₂H₁₄N₂²⁺·2C₇H₃N₂O₆⁻, comprises half a 4-[2-(pyridin-1-ium-4-yl)eth­yl]pyridin-1-ium dication, being disposed about a centre of inversion, and a 2,6-di­nitro­benzoate anion, in a general position. In the anion, the carboxyl­ate group is inclined to the benzene ring [dihedral angle = 85.45 (9)°], whereas near-coplanar and twisted arrangements are found for the nitro groups [O—N—C—C torsion angles = 179.80 (14) and 20.2 (2)°]. In the crystal, three-component aggregates sustained by charge-assisted N⁺—H...O⁻ hydrogen bonds are found and these are consolidated into a three-dimensional architecture by C—H...O and π–π [inter-centroid distances = 3.6796 (14) and 3.7064 (14) Å] inter­actions.