A model for the generic alpha relaxation of viscous liquids

Abstract

Dielectric measurements on molecular liquids just above the glass transition indicate that alpha relaxation is characterized by a generic high-frequency loss varying as ${\omega }^{-1/2}$, whereas deviations from this come from one or more low-lying beta processes [Olsen et al, Phys. Rev. Lett. {\bf 86} (2001) 1271]. Assuming that long-wavelength fluctuations dominate the dynamics, a model for the dielectric alpha relaxation based on the simplest coupling between the density and dipole density fields is proposed here. The model, which is solved in second order perturbation theory in the Gaussian approximation, reproduces the generic features of alpha relaxation.

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Cited by in corpus (11)

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• Supercooled Liquid Dynamics Studied via Shear-Mechanical Spectroscopy
• Solid-that-flows picture of glass-forming liquids
• Solidity of viscous liquids. IV. Density fluctuations
• Ten themes of viscous liquid dynamics
• Solidity of viscous liquids. V. Long-wavelength dominance of the dynamics
• Swap Monte Carlo for diatomic molecules
• Violations of conservation laws in viscous liquid dynamics