Crystal structure of bis(piperazin-1-ium-kappa N-4) bis(thiosulfato-kappa S)zinc(II) dihydrate

In the title compound, [Zn(C4H11N2)2(S2O3)(2)]2.H2O, two thiosulfate ions coordinate to the zinc(II) atom through the terminal S atoms. The tetrahedral coordination around the Zn-II ion is completed by ligating to two N atoms of two piperazinium ions. The remaining two N atoms of the piperazinium ions are diprotonated and do not coordinate to the metal centre. In the crystal, however, they are involved in N - H center dot center dot center dot O-water and N - H center dot center dot center dot Osulfato hydrogen bonds. Together, a series of N - H center dot center dot center dot O and O - H center dot center dot center dot O hydrogen bonds, involving the 0 atoms of the thiosulfate ions and the water molecules as acceptors and the hydrogen atoms of the piperazinium ions and the water molecules as donors, form a three-dimensional supramolecuar structure. Within this framework there are a number of intra- and intermolecular C - H center dot center dot center dot O and C - H center dot center dot center dot S contacts present.