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Structurally determined directionality identifies the boundary between mobile and immobile domains in a disordered
Vanessa K de Souza1, Peter Harrowell
1University Chemical Laboratories, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom.
The Journal of Chemical Physics
|February 11, 2012
Summary
Dynamic heterogeneities in amorphous materials are linked to particle motion directionality. This study proposes directionality arises from single, unconstrained particle movements, exploring its spatial distribution using a random bond model.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Statistical Mechanics
Background:
- Amorphous materials exhibit dynamic heterogeneities.
- Particle motion in these systems can be directional.
Purpose of the Study:
- To propose a new definition for particle directionality in amorphous systems.
- To investigate the spatial distribution of highly directional particles.
Main Methods:
- Utilizing a random bond model.
- Analyzing particle motion and degrees of freedom.
Main Results:
- Directionality is attributed to particles with single, unconstrained motions.
- The spatial distribution of these directional particles is explored.
Conclusions:
- The proposed definition offers insight into particle dynamics in amorphous structures.
- Understanding directionality is key to characterizing amorphous material behavior.
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