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Updated: Jun 26, 2026
08:50
Fabricating Optical-quality Glass Surfaces to Study Macrophage Fusion
Published on: March 14, 2018
On the surface of glasses.
Jacob D Stevenson1, Peter G Wolynes
1Department of Physics, Center for Theoretical Biological Physics, University of California, San Diego, La Jolla, California 92093, USA.
The Journal of Chemical Physics
|December 24, 2008
Summary
Glass surface dynamics are faster than bulk dynamics. Random First Order Transition (RFOT) theory predicts surface energy barriers are half that of the bulk, enhancing mobility and affecting the glass transition temperature.
Area of Science:
- Materials Science
- Physical Chemistry
- Condensed Matter Physics
Background:
- Dynamics near the surface of glasses are significantly faster than in the bulk.
- Understanding surface dynamics is crucial for glass properties and behavior.
Purpose of the Study:
- To investigate the free energy barrier for activated motion near a free surface of glasses.
- To explore the impact of surface mobility on the energy landscape and glass transition.
- To analyze the influence of deposition rate on configurational entropy in vapor-deposited glasses.
Main Methods:
- Utilizing random first order transition (RFOT) theory to model surface dynamics.
- Neglecting static structural perturbations at the surface for simplified calculations.
- Employing mode coupling effects to extend surface mobility into the bulk.
Main Results:
- The free energy barrier for activated motion near a free surface is predicted to be half that of the bulk at the same temperature.
- Increased surface mobility allows layers to descend further on the energy landscape.
- A limiting value for configurational entropy is predicted based on deposition rate.
- Excess free surface mobility can perturb the glass transition temperature into the bulk.
Conclusions:
- Surface dynamics in glasses exhibit significantly enhanced mobility compared to the bulk.
- RFOT theory provides a framework for understanding surface energy barriers and configurational entropy limitations.
- The interplay between surface and bulk dynamics, influenced by mode coupling, can alter the glass transition temperature beyond local scales.
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