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Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Structural and dynamical heterogeneity in a glass-forming liquid
Gurpreet S Matharoo1, M S Gulam Razul, Peter H Poole
1Department of Physics, St. Francis Xavier University, Antigonish, Nova Scotia B2G 2W5, Canada.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 7, 2007
Summary
Spatially correlated clusters of low-potential-energy molecules appear during structural relaxation in glass-forming liquids. These structural heterogeneities are linked to clusters of molecules with low mobility, revealing key insights into glass dynamics.
Area of Science:
- Computational physics
- Materials science
- Chemical physics
Background:
- Glass-forming molecular liquids exhibit complex dynamics and structural properties.
- Understanding the relationship between structure and dynamics is crucial for materials science.
Purpose of the Study:
- To analyze dynamical and structural properties in glass-forming molecular liquids using the isoconfigurational ensemble.
- To investigate the presence and nature of spatial correlations in molecular potential energy and mobility.
Main Methods:
- Utilizing the "isoconfigurational ensemble" simulation technique.
- Analyzing simulations of a glass-forming molecular liquid.
Main Results:
- Spatially correlated clusters of low-potential-energy molecules are observed on the timescale of structural relaxation.
- Absence of spatial correlations in instantaneous potential energy does not preclude correlated structures on longer timescales.
- Observed structural heterogeneities correlate with dynamical heterogeneities, specifically clusters of low molecular mobility.
Conclusions:
- The isoconfigurational ensemble is effective for studying both dynamical and structural properties in glass-forming systems.
- Structural heterogeneities, characterized by low-potential-energy clusters, emerge and are linked to dynamical heterogeneities (low mobility clusters) during relaxation.
- This study provides insights into the cooperative nature of molecular motion and structural organization in glass-forming liquids.
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