Escorted free energy simulations

Suriyanarayanan Vaikuntanathan; Christopher Jarzynski

doi:10.1063/1.3544679

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arXiv · 1101.2612

Escorted free energy simulations

Suriyanarayanan Vaikuntanathan·Christopher Jarzynski

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Abstract

We describe a strategy to improve the efficiency of free energy estimates by reducing dissipation in nonequilibrium Monte Carlo simulations. This strategy generalizes the targeted free energy perturbation approach [Phys. Rev. E. 65, 046122, 2002] to nonequilibrium switching simulations, and involves generating artificial, "escorted" trajectories by coupling the evolution of the system to updates in external work parameter. Our central results are: (1) a generalized fluctuation theorem for the escorted trajectories, and (2) estimators for the free energy difference Delta F in terms of these trajectories. We illustrate the method and its effectiveness on model systems.

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Suriyanarayanan Vaikuntanathan, Christopher Jarzynski. 2011-01-13. Escorted free energy simulations. https://doi.org/10.1063/1.3544679

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