Dielectric secondary relaxation of water in aqueous binary glass-formers.
Glassy aqueous binary mixtures generally exhibit a water induced dielectric relaxation. The characteristic time-scale of this relaxation follows an Arrhenius temperature dependence with a nearly universal activation energy. We here demonstrate for a series of model aqueous mixtures that the relaxation time also follows a remarkably general exponential dependence on the weight fraction of water. By comparison to literature data we show that this behaviour is shared by a wide range of molecular systems. Neither the detailed nature of the water molecules' glassy environment nor the details of the route of formation of the glassy state has a significant effect on the observed behaviour.
Sjöström
Johan
J
Department of Applied Physics, Chalmers University of Technology, SE-41296 Göteborg, Sweden. johan.sjostrom@chalmers.se
Mattsson
Johan
J
Bergman
Rikard
R
Johansson
Erik
E
Josefsson
Karin
K
Svantesson
David
D
Swenson
Jan
J
D017097:Electric Impedance; D005898:Glass / Q000737:chemistry*; D006860:Hydrogen Bonding; D013696:Temperature; D014867:Water / Q000737:chemistry*
D014867:Water