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Updated: May 31, 2026
16:24
Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
Evidence for compact cooperatively rearranging regions in a supercooled liquid
1Department for Numerical Analysis and Computer Science, Royal Institute of Technology, S-100 44 Stockholm, Sweden.
Summary
Structural relaxation in supercooled liquids is delayed during cooling. This occurs because collective particle movements preserve structural correlations within three-dimensional cooperatively rearranging regions.
Area of Science:
- Condensed matter physics
- Materials science
- Computational physics
Background:
- Supercooled liquids exhibit complex dynamics near the glass transition.
- Understanding structural relaxation is key to characterizing glassy materials.
- Ergodic equilibrium is a theoretical benchmark for disordered systems.
Purpose of the Study:
- To investigate structural relaxation dynamics in a supercooled glass-forming liquid.
- To use kinetic energy fluctuations as a measure of approach to equilibrium.
- To identify the underlying mechanisms for delayed structural relaxation.
Main Methods:
- Constant-energy, constant-volume (NVE) molecular dynamics simulations were employed.
- Time correlations of total kinetic energy fluctuations were analyzed.
- Comparison of total structural relaxation with intermediate scattering function decay was performed.
Main Results:
- Structural relaxation was found to be delayed upon cooling.
- This delay was observed in comparison to the decay of specific components of the intermediate scattering function.
- The findings suggest a decoupling between different relaxation processes.
Conclusions:
- Collective particle movements play a crucial role in preserving structural correlations.
- These collective motions occur within three-dimensional cooperatively rearranging regions.
- The study provides insights into the heterogeneous dynamics of supercooled liquids.
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