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Tetra-kis(quinolin-8-olato-κN,O)hafnium(IV) toluene disolvate
J Augustinus Viljoen1, Hendrik G Visser, Andreas Roodt
1Department of Chemistry, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa.
Abstract:
In the title compound, [Hf(C(9)H(6)NO)(4)]·2C(7)H(8), the hafnium metal centre is coordinated by four N,O-donating bidentate quinolin-8-olate ligands arranged to give a square-anti-prismatic coordination polyhedron with a slightly distorted dodeca-hedral geometry. The average Hf-O and Hf-N distances are 2.096 (3) and 2.398 (3) Å, respectively, and the average O-Hf-N bite angle is 70.99 (11)°. The crystal packing is controlled by π-π inter-actions between quinoline ligands of neighbouring mol-ecules and hydrogen-bonding inter-actions. The inter-planar distances vary between 3.138 (1) and 3.208 (2) Å, while the centroid-centroid distances range from 3.576 (1) to 4.074 (1) Å.
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