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arXiv · 0809.2256

Using bijective maps to improve free energy estimates

A. M. Hahn·H. Then
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Abstract

We derive a fluctuation theorem for generalized work distributions, related to bijective mappings of the phase spaces of two physical systems, and use it to derive a two-sided constraint maximum likelihood estimator of their free energy difference which uses samples from the equilibrium configurations of both systems. As an application, we evaluate the chemical potential of a dense Lennard-Jones fluid and study the construction and performance of suitable maps.

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A. M. Hahn, H. Then. 2008-09-12. Using bijective maps to improve free energy estimates. https://doi.org/10.1103/physreve.79.011113

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