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Relation between local diffusivity and local inherent structures in the Kob-Andersen Lennard-Jones model
Emilia La Nave1, Srikanth Sastry, Francesco Sciortino
1Dipartimento di Fisica and CNR-INFM Udr and CRS-SOFT: Complex Dynamics in Structured Systems, Università di Roma La Sapienza, Piazzale Aldo Moro 2, I-00185 Roma, Italy.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 7, 2007
Summary
We analyzed particle dynamics to link temperature and potential energy landscape depth to diffusion. This reveals how basin exploration explains supercooled states and dynamic heterogeneities.
Area of Science:
- Condensed matter physics
- Computational chemistry
- Statistical mechanics
Background:
- Understanding particle dynamics in complex systems is crucial.
- The potential energy landscape framework connects system structure to dynamics.
- Supercooled states exhibit unique and heterogeneous dynamics.
Purpose of the Study:
- To model-free separate the effects of temperature and potential energy landscape basin depth on particle dynamics.
- To establish a connection between thermodynamics and dynamics within the potential energy landscape framework.
- To interpret the dynamic behavior in supercooled states and dynamic heterogeneities.
Main Methods:
- Analysis of one thousand independent equilibrium trajectories.
- Simulation of a system containing 155 Lennard-Jones particles.
- Model-free separation of temperature and basin depth influences.
Main Results:
- The diffusion coefficient (D) can be estimated as a sum of contributions from sampled basins.
- A direct link between thermodynamics and dynamics in the potential energy landscape was established.
- Nonlinearity between local diffusion and basin depth explains supercooled dynamics and dynamic heterogeneities.
Conclusions:
- The study successfully disentangles the roles of temperature and landscape exploration in particle dynamics.
- The findings provide a new perspective on the behavior of matter in supercooled states.
- This work offers a framework for understanding dynamic heterogeneities in complex systems.
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