Crystal structure and Hirshfeld surface analysis of ethane-1,2-diaminium 3-[2-(1,3-dioxo-1,3-di-phenyl-propan-2-yl-idene)hydrazin-yl]-5-nitro-2-oxido-benzene-sulfonate dihydrate.

In the anion of the title hydrated salt, C(2)H(10)N(2)(2+)·C(21)H(13)N(3)O(8)S(2-)·2H(2)O, the planes of the phenyl rings and the benzene ring of the 5-nitro-2-oxido-benzene-sulfonate group are inclined to one another by 44.42†(11), 56.87†(11) and 77.70†(12)°. In the crystal, the anions are linked to the cations and the water mol-ecules by N-H⋯O and O-H⋯O hydrogen bonds, forming a three-dimensional network. Furthermore, there are face-to-face π-π stacking inter-actions between the centroids of one phenyl ring and the benzene ring of the 5-nitro-2-oxido-benzene-sulfonate group [centroid-centroid distance = 3.8382†(13)†à and slippage = 1.841†à ]. A Hirshfeld surface analysis was conducted to verify the contributions of the different inter-molecular inter-actions.