Universal nonexponential relaxation: Complex dynamics in simple liquids.
The dynamics of the noble-gas liquids underlies that of all liquids making them an important prototypical model system. Using optical Kerr-effect spectroscopy we show that for argon, krypton, and xenon, both the librational and diffusional contributions to the spectrum are surprisingly complex. The diffusional relaxation appears as a stretched-exponential, such as widely found in studies of structured (e.g., glass-forming) liquids and as predicted by mode-coupling theory. We show that this behavior is remarkably similar to that measured in water and suggest that it is a fundamental or universal property.
Turton
David A
DA
Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG, United Kingdom. david.turton@phys.strath.ac.uk
Wynne
Klaas
K