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arXiv · 1106.4994

Approaching a parameter-free metadynamics

Bradley M. Dickson
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Abstract

We present a unique derivation of metadynamics. The starting point for the derivation is an on-the-fly reweighting scheme but through an approximation we recover the standard metadynamics and the well-tempered metadynamics in a general form while never appealing to the extended Lagrangian framework. This work leads to a more robust understanding of the error in the computed free energy than what has been obtained previously. Moreover, a formula for the exact free energy is introduced. The formula can be used to post-process any existing well-tempered metadynamics data allowing one, in principle, to obtain an exact free energy regardless the metadynamics parameters.

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Bradley M. Dickson. 2011-08-10. Approaching a parameter-free metadynamics. https://doi.org/10.1103/physreve.84.037701

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