Title: Rotational diffusion of a nonpolar and a dipolar solute in 1-butyl-3-methylimidazolium hexafluorophosphate and glycerol: Interplay of size effects and specific interactions
Authors: Mali, Kunal
Dutt, G. B ×
Mukherjee, T #
Issue Date: Feb-2008
Publisher: Amer inst physics
Series Title: Journal of Chemical Physics vol:128 issue:5
Article number: 054504
Abstract: Temperature dependent rotational diffusion of a nonpolar solute, 9-phenylanthracene (9-PA), and a dipolar solute, rhodamine 110 (R110), has been examined in an ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim(+)][PF6-]) and in a conventional solvent, glycerol. This study has been undertaken to explore how parameters such as solvent size and free volume influence solute rotation in the case of a nonpolar solute, 9-PA. To understand the role of specific solute-solvent interactions, similar measurements have been performed with a dipolar analogue, R110. It has been observed that the viscosity normalized reorientation times of 9-PA are longer by a factor of 1.4-1.6 in glycerol compared to those in [bmim(+)][PF6-]. While the most commonly used Stokes-Einstein-Debye hydrodynamic theory is not successful in explaining this experimental observation, Gierer-Wirtz and Dote-Kivelson-Schwartz quasihydrodynamic theories could rationalize this trend, albeit in a qualitative manner. Rotational diffusion of R110, on the other hand, follows an exactly opposite trend compared to 9-PA. The normalized reorientation times of R110 are longer by a factor of 1.3-1.4 in [bmim(+)][PF6-] compared to glycerol, which is due to the formation of stronger solute-solvent hydrogen bonds between the positively charged R110 and the ionic liquid. (c) 2008 American Institute of Physics.
ISSN: 0021-9606
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Molecular Imaging and Photonics
× corresponding author
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science