title: Tetra-kis(5,7-dimethyl-quinolin-8-olato-κN,O)hafnium(IV) dimethyl-formamide disolvate.
abstract: In the title compound, [Hf(C(11)H(10)NO)(4)]·2C(3)H(7)NO, the Hf(IV) atom is coordinated by four N,O-donating bidentate 5,7-dimethyl-8-quinolino-late (Ox(-)) ligands arranged to give a distorted square-anti-prismatic coordination polyhedron. The average Hf-O and Hf-N distances are 2.098 and 2.298 Å, respectively, and the average O-Hf-N bite angle is 70.2°. The crystal packing is controlled by π-π inter-actions between Ox(-) ligands of neighbouring mol-ecules, giving rise to a three-dimensional supra-molecular grid network. The inter-planar distances vary from 3.441 (1) to 3.509 (1) Å, while the centroid-centroid distances vary from 3.688 (2) to 3.759 (12) Å. A non-classical C-H⋯O hydrogen bond is observed between the complex and one of the solvate mol-ecules.
authors: Department of Chemistry, University of the Free State, P.O. Box 339, Bloemfontein, 9300,  South Africa.
authors: J Augustinus
authors: JA
authors: Viljoen
authors: Hendrik G
authors: HG
authors: Visser
authors: Andreas
authors: A
authors: Roodt