File Download

There are no files associated with this item.

  • Find it @ UNIST can give you direct access to the published full text of this article. (UNISTARs only)
Related Researcher

BielawskiChristopher W

Bielawski, Christopher W.
Read More

Views & Downloads

Detailed Information

Cited time in webofscience Cited time in scopus
Metadata Downloads

Measuring Molecular Dynamics and Activation Energies for Quaternary Acyclic Ammonium and Cyclic Pyrrolidinium Ionic Liquids Using14N NMR Spectroscopy

Author(s)
Alam, Todd M.Dreyer, Daniel R.Bielawski, Christopher W.Ruoff, Rodney S.
Issued Date
2011-05
DOI
10.1021/jp200630k
URI
https://scholarworks.unist.ac.kr/handle/201301/33188
Fulltext
https://pubs.acs.org/doi/10.1021/jp200630k
Citation
JOURNAL OF PHYSICAL CHEMISTRY A, v.115, no.17, pp.4307 - 4316
Abstract
The N-14 NMR spin-lattice (R-1) and spin-spin (R-2) relaxation rates were determined as a function of temperature for a series of tetra-alkyl acyclic ammonium and cyclic pyrrolidinium ionic liquids (ILs). Through the use of the R-2/R-1, ratio method, it was shown that for the majority of these ILs, the reorientational dynamics are not in the extreme narrowing regime, but instead are in the dispersive relaxation regime, thus allowing a unique solution for the correlation time to be determined. The temperature variation of the R-2 relaxation rate, along with the temperature variation of the calculated correlation times, allowed activation energies for the reorientational dynamics to be measured and compared. In addition, these NMR relaxation experiments enabled the N-14 quadrupolar coupling product to be extracted, which revealed surprising temperature dependence. Collectively, the N-14 NMR results allow the impact of cation and anion identity on the local reorientational dynamics of these ILs to be delineated.
Publisher
American Chemical Society (ACS)
ISSN
1089-5639
Keyword
QUADRUPOLE COUPLING-CONSTANTSTEMPERATURE-DEPENDENCEPHYSICOCHEMICAL PROPERTIESNUCLEAR-RELAXATIONSELF-DIFFUSIONC-13REORIENTATIONORGANIZATIONTIMESROTATIONAL FRICTION COEFFICIENTS

qrcode

Items in Repository are protected by copyright, with all rights reserved, unless otherwise indicated.