Quasielastic neutron scattering studies on glass-forming ionic liquids with imidazolium cations.

@article{Kofu2015QuasielasticNS,
  title={Quasielastic neutron scattering studies on glass-forming ionic liquids with imidazolium cations.},
  author={Maiko Kofu and Madhusudan Tyagi and Yasuhiro Inamura and Kyoko Miyazaki and Osamu Yamamuro},
  journal={The Journal of chemical physics},
  year={2015},
  volume={143 23},
  pages={
          234502
        }
}
Relaxation processes for imidazolium-based ionic liquids (ILs) were investigated by means of an incoherent quasielastic neutron scattering technique. In order to clarify the cation and anion effects on the relaxation processes, ten samples were measured. For all of the samples, we found three relaxations at around 1 ps, 10 ps, and 100 ps-10 ns, each corresponding to the alkyl reorientation, the relaxation related to the imidazolium ring, and the ionic diffusion. The activation energy (Ea) for… 
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Molecular-dynamics simulations on the mesophase transition induced by oscillatory shear in imidazolium-based ionic liquid crystals.
TLDR
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References

SHOWING 1-10 OF 83 REFERENCES
Heterogeneous slow dynamics of imidazolium-based ionic liquids studied by neutron spin echo.
TLDR
There exist two parts in ILs: one with the ordered nanostructure exhibiting the slow relaxation, and the other with disordered structure showing faster relaxation, according to neutron diffraction and neutron spin echo techniques.
Systematic dielectric and NMR study of the ionic liquid 1-alkyl-3-methyl imidazolium.
  • Kenji Nakamura, T. Shikata
  • Chemistry, Physics
    Chemphyschem : a European journal of chemical physics and physical chemistry
  • 2010
TLDR
The dynamic behaviors of ionic liquid samples consisting of a series of 1-alkyl-3-methylimidazolium cations and various counteranionic species are investigated systematically over a wide frequency range using dielectric relaxation (DR) and nuclear magnetic resonance (NMR) spectroscopies.
Dielectric response of imidazolium-based room-temperature ionic liquids.
TLDR
The missing high-frequency portion of the spectra indicates relaxation beyond the upper cutoff frequency of 20 GHz, presumably due to subpicosecond translational and librational displacements of ions in the cage of their counterions, but there is no evidence for orientational relaxation of long-lived ion pairs.
Hierarchical structure and dynamics of an ionic liquid 1-octyl-3-methylimidazolium chloride.
TLDR
This is the first report to clarify temperature dependence of the hierarchical structure and relaxations simultaneously for a typical ionic liquid.
Insights into the interplay between molecular structure and diffusional motion in 1-alkyl-3-methylimidazolium ionic liquids: a combined PFG NMR and X-ray scattering study.
TLDR
The results indicate that this controversial behavior can be rationalized in terms of different types of cation-cation and anion-anion orderings, as revealed by a detailed analysis of the correlation lengths and their dispersion curves obtained from SAXS data.
Relationship between mesoscale dynamics and shear relaxation of ionic liquids with long alkyl chain.
TLDR
The role of the pre-peak structure in the mechanism of shear viscosity of ionic liquids is discussed based on the comparison between NSE and shear relaxations.
Nanostructural organization in ionic liquids.
TLDR
As the length of the alkyl chain increases, the nonpolar domains become larger and more connected and cause swelling of the ionic network, in a manner analogous to systems exhibiting microphase separation.
Local order and long range correlations in imidazolium halide ionic liquids: a combined molecular dynamics and XAS study.
TLDR
A very good agreement between theoretical and experimental EXAFS signals has been obtained, allowing us to assess the reliability of the MD structural results for all the alkylimidazolium halide ILs investigated in this work.
Nanoscale heterogeneity in alkyl-methylimidazolium bromide ionic liquids.
TLDR
In the partial structure analysis of the AMD results, a distinct peak develops at the leading edge of the ring-ring pair distribution function and shifts to lower r with increasing alkyl chain length, indicating that the preferential parallel and antiparallel alignment of neighboring cation rings plays a larger role with increasing chain length.
Structure of ionic liquids of 1-alkyl-3-methylimidazolium cations: a systematic computer simulation study.
TLDR
Partial structure factors of 1-butyl- and 1-octyl- derivatives display a peak at a wave vector smaller than the main peak, indicating the occurrence of an intermediate range order in these ionic liquids due to the presence of long alkyl chains.
...
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