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Time evolution of dynamic propensity in a model glass former: the interplay between structure and dynamics
J A Rodriguez Fris1, L M Alarcón, G A Appignanesi
1Departamento de Química and INQUISUR, Fisicoquímica, Universidad Nacional del Sur, Av. Alem 1253, 8000 Bahía Blanca, Argentina. rodriguezfris@plapiqui.edu.ar
The Journal of Chemical Physics
|January 22, 2009
Summary
Glass-forming systems relax via metabasin hopping. Particle motion propensity changes significantly only after collective rearrangements (d-clusters) occur, decoupling local structural influences.
Area of Science:
- Materials Science
- Computational Chemistry
- Statistical Mechanics
Background:
- Glass-forming systems exhibit complex relaxation dynamics.
- Potential energy landscapes of glasses feature multiple metabasins.
- Collective rearrangements, termed d-clusters, drive relaxation dynamics.
Purpose of the Study:
- To investigate the evolution of particle motion propensity during glass relaxation.
- To understand the role of d-clusters in altering the system's dynamics.
- To correlate particle propensity changes with participation in d-clusters.
Main Methods:
- Isoconfigurational ensemble method.
- Analysis of potential energy surface (PES) and metabasin transitions.
- Tracking spatial distribution and changes in particle propensity.
Main Results:
- The spatial distribution of motion propensity remains stable until a d-cluster event.
- D-cluster formation significantly decorrelates particle propensities.
- Particles involved in d-clusters exhibit substantial changes in their motion propensity.
Conclusions:
- D-cluster events are critical in decoupling particles from local metabasin structures.
- Particle propensity changes are directly linked to their involvement in collective relaxation events.
- This work provides insights into the microscopic mechanisms governing glass relaxation.
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