Dielectric and conductivity relaxation in mixtures of glycerol with LiCl
Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86135, Augsburg, Germany
Accepted: 10 July 2008
Published online: 29 August 2008
We report a thorough dielectric characterization of the α relaxation of glass-forming glycerol with varying additions of LiCl. Nine salt concentrations from 0.1 to 20mol% are investigated in a frequency range of 20Hz-3GHz and analyzed in the dielectric loss and modulus representation. Information on the dc conductivity, the dielectric relaxation time (from the loss) and the conductivity relaxation time (from the modulus) is provided. Overall, with increasing ion concentration, a transition from reorientationally to translationally dominated behavior is observed and the translational ion dynamics and the dipolar reorientational dynamics become successively coupled. This gives rise to the prospect that, by adding ions to dipolar glass formers, dielectric spectroscopy may directly couple to the translational degrees of freedom determining the glass transition, even in frequency regimes where usually strong decoupling is observed.
PACS: 64.70.pm Liquids – / 66.10.Ed Ionic conduction – / 77.22.Gm Dielectric loss and relaxation –
© Springer, 2008