Universal nonexponential relaxation: Complex dynamics in simple liquids
Abstract
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.
- Publication:
-
Journal of Chemical Physics
- Pub Date:
- November 2009
- DOI:
- Bibcode:
- 2009JChPh.131t1101T
- Keywords:
-
- argon;
- diffusion;
- krypton;
- librational states;
- liquid structure;
- liquid theory;
- optical Kerr effect;
- vibrational modes;
- xenon;
- 66.10.C-;
- 61.20.-p;
- 61.25.-f;
- Diffusion and thermal diffusion;
- Structure of liquids;
- Studies of specific liquid structures