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Updated: May 31, 2026

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
A study of out-of-plane cation dynamics in a bis-thiourea pyridinium chloride inclusion compound
A Pajzderska1, P Czarnecki, J P Embs
1Faculty of Physics, A. Mickiewicz University, Poznań, Poland. apajzder@amu.edu.pl
Abstract:
The out-of-plane motion of the pyridinium cation in the bis-thiourea pyridinium chloride inclusion compound has been studied in a wide temperature range using (1)H NMR, dielectric spectroscopy and quasielastic neutron scattering. The geometry of this motion is obtained from the Q-dependence of the elastic incoherent structure factor determined from the quasielastic neutron scattering measurements. We find that the pyridinium cation performs out-of-plane reorientations around the axis passing through two opposite atoms of the ring. The correlation times as a function of temperature were measured in the three known crystallographic phases, finding a good agreement between the three techniques employed. The activation energy for this motion changes from 5 ± 1 kJ mol(-1) in the low-temperature phase to 1.2 ± 0.2 kJ mol(-1) in the intermediate and high-temperature phases.
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