Hexaaqua­zinc(II) bis­[trichloro­(3,7‐dihydro‐1,3,7‐trimethyl‐1H‐purine‐2,6‐dione‐κN9)zincate(II)] dihydrate

The title compound, [Zn(H2O)6][ZnCl3(C8H10N4O2)]2·2H2O, consists of two disordered water mol­ecules, one hexa­hydrated ZnII cation and two [ZnIICl3(caffeine)]− anions, which are arranged around an inversion center. The coordination around the hexa­hydrated ZnII cation is octa­hedral. This cation is linked with [ZnIICl3(caffeine)]− anions and water mol­ecules via O—H⋯O hydrogen bonds. Moreover, O—H⋯O and O—H⋯Cl hydrogen bonds are co-operative in building up two-dimensional bilayers in which hexa­hydrated ZnII cations are sandwiched between two layers of [ZnIICl3(caffeine)]− anions, which are anti-parallel to each other.

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