trans-2,5-Di­methyl­piperazine-1,4-diium bis(perchlorate) dihydrate: crystal structure and Hirshfeld surface analysis

The asymmetric unit of the title hydrated mol­ecular salt, C(6)H(16)N(2) (2+)·2ClO(4) (−)·2H(2)O, contains a half dication (completed by inversion symmetry), a perchlorate anion and a water mol­ecule. The extended structure consists of infinite chains of formula [(ClO(4))H(2)O](n)(n) (−) ions extending along the b axis linked by O(w)—H⋯O (w = water) hydrogen bonds. These chains are cross-linked by the dications via N—H⋯O(w) and weak C—H⋯O hydrogen bonds, thus forming a three-dimensional supra­molecular network. Three-dimensional Hirshfeld surface analysis and two-dimensional fingerprint maps reveal that the structure is dominated by H⋯O/O⋯H and H⋯H contacts.