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Updated: Oct 11, 2025
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Crystal structures of Zn(cyclam)I2 (second monoclinic polymorph) and Zn(cyclam)I(I3)
Sergey P Gavrish1, Sergiu Shova2, Yaroslaw D Lampeka1
1L.V. Pisarzhevskii Institute of Physical Chemistry of the National Academy of Sciences of Ukraine, Prospekt Nauki 31, Kyiv 03028, Ukraine.
Abstract:
The asymmetric unit of the first title compound iodido-(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4 N 1,N 4,N 8,N 11)zinc(II) iodide, [ZnI(C10H24N4)]I, I, consists of the zinc-cyclam macrocyclic cation with one iodide anion coordinated to the metal ion [Zn-I = 2.6619 (5) Å] and the second present as a counter-ion. The asymmetric unit of the second title compound iodido-(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4 N 1,N 4,N 8,N 11)zinc(II) triiodide, [ZnI(C10H24N4)]I3, II, consists of half of the centrosymmetric macrocyclic cation, in which the ZnII ion coordinated to an iodide anion [Zn-I = 2.766 (2) Å] is disordered over two positions [Zn⋯Zn = 0.810 (3) Å], and of the two halves of the crystallographically non-equivalent, non-coordinated, centrosymmetric triiodide anions. In both compounds, the N,N,N,N-tetra-dentate macrocyclic ligand is present in the most energetically favored trans-III conformation. In the crystals of I, the [Zn(C10H24N4)I]+ cations and the non-coordinated iodide anions are linked by N-H⋯I and bifurcated N-H⋯(I,I) hydrogen bonds, resulting in the formation of two-dimensional networks lying parallel to the (001) and (101) planes. In contrast, the crystals of II are built up from infinite chains of the five-coordinate macrocyclic units arranged along the b-axis direction and perpendicular sheets formed of the triiodide counter-ions without significant hydrogen bonding between them.
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