ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY, vol.60, 2004 (SCI-Expanded)
The crystal structure of the title compound, [Ni(NCS)(2)(C4H12N2O)(2)], has two crystallographically independent half-molecules in the asymmetric unit, with each Ni atom residing on a centre of symmetry. The two molecules exhibit similar coordination geometry but display differences with regard to other structural features. Each Ni-II centre is octahedrally coordinated by two mutually trans chelating hydroxyethylethylenediamine ligands and two mutually trans isothiocyanate ions. The two independent molecules form chains through different types of non-covalent interactions. In the case of one of the molecules, only NCS and free OH groups participate in hydrogen bonding, while in the chain based on the second molecule, the NCS, NH, NH2 and free OH groups are involved in intermolecular hydrogen bonding. The two chains interact with one another through hydrogen bonding, forming planar sheets. The third packing direction is mediated only by van der Waals interactions.