Diffusion in Ionic Liquids: The Interplay between Structure and Dynamics,
J. R. Sangoro, C. Iacob, S. Naumov, R. Valiullin, H. Rexhausen, J. Hunger, R. Buchner,
V. Strehmel, J. Kärger, and F. Kremer,
Soft Matter 7 (2011) 1678-11681. DOI: 10.1039/c0sm01404d
Abstract
Diffusion in a series of ionic liquids is investigated by a combination of Broadband Dielectric
Spectroscopy (BDS) and Pulsed Field Gradient Nuclear Magnetic Resonance (PFG NMR). It is demonstrated
that the mean jump lengths increase with the molecular volumes determined from quantum-chemical
calculations. This provides a direct means-via Einstein-Smoluchowski relation-to determine the diffusion
coefficient by BDS over more than 8 decades unambiguously and in quantitative agreement with PFG NMR
measurements. New possibilities in the study of charge transport and dynamic glass transition in ionic
liquids are thus opened. |
