Poly[aqua(μ2-4,4′-bipyridine-κ2 N:N′)(ethane-1,2-diol-κO)(μ2-sulfato-κ2 O:O′)nickel(II)]

The title compound, [Ni(SO4)(C10H8N2)(C2H6O2)(H2O)]n, contains two crystallographically unique NiII atoms, each lying on a twofold rotation axis and having a slightly distorted octahedral environment. It is isotypic with the previously reported CuII analog [Zhong et al. (2011 ▶). Acta Cryst. C67, m62–m64]. One NiII atom is coordinated by two N atoms from two bridging 4,4′-bipyridine (4,4′-bipy) ligands, two O atoms from two sulfate ions and two aqua O atoms. The second NiII atom is surrounded by two N atoms from 4,4′-bipy ligands and four O atoms, two from bridging sulfate ions and from two ethane-1,2-diol ligands. The sulfate anion acts as a bridging ligand, linking adjacent NiII atoms, leading to the formation of linear ⋯Ni1—Ni2—Ni1—Ni2⋯ chains along the a-axis direction. Adjacent chains are further bridged by 4,4′-bipy ligands, resulting in a two-dimensional layered polymer parallel to (001). In the crystal, the polymeric layers are linked by extensive O—H⋯O hydrogen-bonding interactions involving the O atoms of the water molecules and the ethane-1,2-diol molecules, resulting in a three-dimensional supramolecular network.

The title compound, [Ni(SO 4 )(C 10 H 8 N 2 )(C 2 H 6 O 2 )(H 2 O)] n , contains two crystallographically unique Ni II atoms, each lying on a twofold rotation axis and having a slightly distorted octahedral environment. It is isotypic with the previously reported Cu II analog [Zhong et al. (2011). Acta Cryst. C67, m62-m64]. One Ni II atom is coordinated by two N atoms from two bridging 4,4 0 -bipyridine (4,4 0 -bipy) ligands, two O atoms from two sulfate ions and two aqua O atoms. The second Ni II atom is surrounded by two N atoms from 4,4 0 -bipy ligands and four O atoms, two from bridging sulfate ions and from two ethane-1,2-diol ligands. The sulfate anion acts as a bridging ligand, linking adjacent Ni II atoms, leading to the formation of linear Á Á ÁNi1-Ni2-Ni1-Ni2Á Á Á chains along the a-axis direction. Adjacent chains are further bridged by 4,4 0 -bipy ligands, resulting in a two-dimensional layered polymer parallel to (001). In the crystal, the polymeric layers are linked by extensive O-HÁ Á ÁO hydrogen-bonding interactions involving the O atoms of the water molecules and the ethane-1,2-diol molecules, resulting in a three-dimensional supramolecular network.

Related literature
For Ni-(4,4 0 -bipy) complexes with perchlorate, citraconate or phthalate anions and a water molecule as a second ligand, see:
The single-crystal X-ray diffraction experiment revealed that the title compound is isostructural to the previously reported Cu II analog (Zhong et al., 2011). It contains two crystallographically independent Ni II centres. Atom Ni1 adopts a slightly distorted octahedral geometry. It is coordinated by two N atoms (N1 and N2) from two bridging 4,4′-bipy ligands leading to a layered structure (Fig. 2). Intermolecular O1W-H5C···O6 and O5-H6···O1 hydrogen bonds help to further stabilize the layered structure (Table 2). In the crystal structure, extensive O-H···O hydrogen-bonding interactions between the water molecules, sulfate anions and 1,2-ethanediol molecules result in a three-dimensional supramolecular network.

Experimental
Green block-shaped crystals of the title compound were obtained by a procedure similar to that described previously in

Refinement
All non-hydrogen atoms were refined anisotropically. The aromatic H atoms were positioned geometrically and allowed to ride on their parent atoms, with C-H = 0.93 Å and U iso (H) = 1.2U eq (C