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A "fast growth" method of computing free energy differences

D. A. Hendrix·C. Jarzynski
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Abstract

Let Delta F be the free energy difference between two equilibrium states of a system. An established method of numerically computing Delta F involves a single, long ``switching simulation'', during which the system is driven reversibly from one state to the other (slow growth, or adiabatic switching). Here we study a method of obtaining the same result from numerous independent, irreversible simulations of much shorter duration (fast growth). We illustrate the fast growth method, computing the excess chemical potential of a Lennard-Jones fluid as a test case, and we examine the performance of fast growth as a practical computational tool.

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BibTeXRIS

D. A. Hendrix, C. Jarzynski. 2001-01-19. A "fast growth" method of computing free energy differences. https://doi.org/10.1063/1.1353552

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