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Enhanced sampling of nonequilibrium steady states
1Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA.
Annual Review of Physical Chemistry
|April 7, 2010
Summary
This review covers advanced simulation techniques, nonequilibrium umbrella sampling (NEUS) and forward flux sampling (FFS), for studying systems far from equilibrium. These methods enhance the computation of transition rates and steady-state averages by analyzing dynamical paths.
Area of Science:
- Computational Physics
- Chemical Physics
- Statistical Mechanics
Background:
- Simulating complex nonequilibrium systems is computationally challenging.
- Accurate calculation of transition rates and steady-state averages requires efficient sampling of rare events.
- Existing methods may struggle with systems driven far from equilibrium.
Purpose of the Study:
- To review recent advancements in accelerating simulations of nonequilibrium systems.
- To compare nonequilibrium umbrella sampling (NEUS) and forward flux sampling (FFS).
- To highlight the application of these methods for calculating transition rates.
Main Methods:
- Focusing on nonequilibrium umbrella sampling (NEUS) and forward flux sampling (FFS).
- Discussing NEUS advancements, including string methods for enhanced phase space exploration.
- Recasting FFS within the NEUS framework for direct comparison.
Main Results:
- Recent NEUS developments enable efficient sampling of complex systems via manifold (string) approximations.
- The two-string extension of NEUS allows separate treatment of forward and backward transition ensembles.
- Recasting FFS within NEUS facilitates a unified understanding and comparison of the methods.
Conclusions:
- NEUS and FFS are powerful tools for simulating systems far from equilibrium.
- Advancements in NEUS offer improved efficiency and applicability to complex systems.
- Further research and applications are expected in this domain.
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