catena-Poly[[[diaqua-(tetra-methyl-ethylenediamine-κ(2) N,N')nickel(II)]-μ-sulfato-κ(2) O:O'] monohydrate].

The title compound, {[Ni(SO4)(C6H16N2)(H2O)2]·H2O} n , contains a Ni(II) atom that is coordinated nearly octa-hedrally by a chelating tetra-ethyl-enediamine (tmeda) ligand, two water mol-ecules in a cis arrangement and two O atoms of two sulfate anions in a trans arrangement. The sulfate anions act as μ2-bridging ligands leading to a chain structure of alternating NiO4N2 octa-hedra and SO4 tetra-hedra parallel to [001]. The polymeric chains are linked by O-H⋯O hydrogen bonds between coordinating water mol-ecules and sulfate anions to give double strands.