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Updated: Dec 27, 2025
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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Rotational and translational dynamics in dense fluids of patchy particles
Susana Marín-Aguilar1, Henricus H Wensink1, Giuseppe Foffi1
1Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France.
The Journal of Chemical Physics
|March 2, 2020
Summary
Directionality impacts relaxation in glassy systems. Rotational relaxation is faster than translational, with icosahedral structures significantly slowing dynamics at low temperatures.
Area of Science:
- Condensed matter physics
- Computational materials science
- Statistical mechanics
Background:
- Glassy systems exhibit complex dynamics.
- Directionality in particle interactions influences system behavior.
- Patchy particles offer a model for studying anisotropic interactions.
Purpose of the Study:
- To investigate the effect of particle directionality on rotational and translational relaxation in glassy systems.
- To analyze how different patch geometries influence local structure and dynamics.
- To compare simulation results with a simplified dynamical model.
Main Methods:
- Molecular dynamics simulations of patchy particle systems.
- Analysis of rotational and translational relaxation times.
- Comparison with a dynamical Monte Carlo model.
- Varying patch geometries and system temperatures.
Main Results:
- Rotational relaxation occurs significantly faster than translational relaxation across most conditions.
- Icosahedral patch geometry enhances local structure, leading to a pronounced slowdown in dynamics at low temperatures.
- An intermediate patch size showed the strongest slowing effect.
Conclusions:
- Rotational diffusion is largely independent of the slower, cage-breaking dynamics required for translation.
- The local structural arrangement, particularly icosahedral ordering, is crucial for understanding relaxation dynamics in glassy systems.
- Directionality and specific patch design can be used to tune the dynamics of soft glassy materials.
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