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Updated: Jun 2, 2026
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Dipotassium hexa-aqua-nickel(II) bis-[hexa-fluoridozirconate(IV)]
Abdelghani Oudahmane1, Noura Mnaouer, Malika El-Ghozzi
1Université Blaise Pascal, Laboratoire des Matériaux Inorganiques, UMR CNRS 6002, 24 Avenue des Landais, 63177 Aubière, France.
Abstract:
Single crystals of the title compound, K(2)[Ni(H(2)O)(6)][ZrF(6)](2), were grown by slow evaporation of a 40% aqueous HF solution in which a stoichiometric mixture of NiCl(2)·6H(2)O, ZrF(4) and KCl was dissolved. The monoclinic structure is isotypic with its K(2)Cu, K(2)Zn, Cs(2)Zn and Cs(2)Cu analogues. The structure is built up from isolated, slightly elongated octa-hedral [Ni(H(2)O)(6)](2+) complex cations (symmetry ) and dimeric [Zr(2)F(12)](4-) complex anions (symmetry ) that are also isolated from each other. The [Zr(2)F(12)](4-) anion results from the association of two distorted penta-gonal-bipyramidal [ZrF(7)] coordination polyhedra by sharing an equatorial edge passing through an inversion center of the unit cell. Both isolated [Ni(H(2)O)(6)](2+) and [Zr(2)F(12)](4-) complex ions are situated in planes parallel to (010). They are connected by the eight-coordinated K(+) ions into a three-dimensional structure. An intricate O-H⋯F hydrogen-bonding network consolidates the structure.
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