Ion channels and anisotropic ion mobility in a liquid-crystalline columnar phase as observed by multinuclear NMR diffusometry

J Phys Chem B. 2010 Dec 2;114(47):15477-82. doi: 10.1021/jp1082054. Epub 2010 Nov 5.

Abstract

The anisotropic diffusion of anions and cations in the columnar and isotropic phases of a fan-shaped imidazolium hexafluorophosphate salt is measured by (1)H and (19)F diffusion NMR experiments. The macroscopic orientation of the columnar phase is investigated by (2)H NMR spectroscopy. We find that the anions, confined by the cations, diffuse faster than the cations along the columns but slowly across them, which exemplifies the ion channel model of these materials. The cations and anions are dissociated in the columnar phase but are paired or clustered in the isotropic phase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Diffusion
  • Fluorine / chemistry
  • Ions / chemistry*
  • Liquid Crystals*
  • Models, Chemical
  • Nuclear Magnetic Resonance, Biomolecular

Substances

  • Ions
  • Fluorine