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Updated: Jul 13, 2026
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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Do short-time fluctuations predict the long-time dynamic heterogeneity in a supercooled liquid?
J A Rodriguez Fris1, L M Alarcón, G A Appignanesi
1Fisicoquímica, Departamento de Química, Universidad Nacional del Sur, Avenida Alem 1253, 8000 Bahía Blanca, Argentina.
Summary
Short-time fluctuations in supercooled liquids predict intermediate-time dynamics, not long-time alpha-relaxation. Dynamics become unpredictable at longer timescales, aligning with a metabasin random walk model.
Area of Science:
- Condensed Matter Physics
- Physical Chemistry
- Computational Materials Science
Background:
- Supercooled liquids exhibit complex dynamics.
- Short-time fluctuations have been proposed as predictors of long-time dynamics.
- The relationship between local structure, short-time dynamics, and long-time mobility is not fully understood.
Purpose of the Study:
- To investigate whether short-time fluctuations in supercooled liquids can predict long-time dynamic propensity.
- To determine the time scales over which local structure influences dynamics.
- To clarify the predictability of supercooled liquid dynamics.
Main Methods:
- Analysis of short-time fluctuations in supercooled liquids.
- Comparison of dynamics at different time scales (metabasin lifetime vs. alpha-relaxation time).
- Investigating the influence of local structure on particle motion.
Main Results:
- Short-time fluctuations predict dynamics at intermediate times (metabasin lifetime).
- The influence of local structure on dynamics is limited in time, fading before alpha-relaxation.
- Long-time dynamics (alpha-relaxation) are unpredictable from short-time behavior.
Conclusions:
- Short-time dynamics are precursors to intermediate-time mobility in supercooled liquids.
- Long-time dynamics, specifically alpha-relaxation, are not predictable from initial short-time fluctuations.
- The findings support a metabasin random walk scenario for supercooled liquid dynamics.
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