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?-Meta Dynamics Approach To Compute Absolute Solvation Free Energy.

ABSTRACT: We present a new approach to combine ? dynamics with meta-dynamics (named ?-meta dynamics) to compute free energy surface with respect to ?. Particularly, the ?-meta dynamics method extends meta-dynamics to a single virtual variable ?, i.e., the coupling parameter between solute and solvent, to compute absolute solvation free energy as an exemplary application. We demonstrate that ?-meta dynamics simulations can recover the accurate potential of mean force surface with respect to ? compared to the benchmark results from traditional ?-dynamics with umbrella sampling. The solvation free energy results for five small organic molecules from ?-meta dynamics simulations using the same filling scheme show that the statistical errors are within ±0.5 kcal/mol. The new ?-meta dynamics method is general and other variables such as order parameters to describe conformational changes can be easily combined with ?-meta dynamics. This should allow for efficient samplings on high-dimension free energy landscapes.

SUBMITTER: Wu P

PROVIDER: S-EPMC3652470 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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λ-Meta Dynamics Approach To Compute Absolute Solvation Free Energy.

Wu Pan P Hu Xiangqian X Yang Weitao W

The journal of physical chemistry letters 20110901 17

We present a new approach to combine λ dynamics with meta-dynamics (named λ-meta dynamics) to compute free energy surface with respect to λ. Particularly, the λ-meta dynamics method extends meta-dynamics to a single virtual variable λ, i.e., the coupling parameter between solute and solvent, to compute absolute solvation free energy as an exemplary application. We demonstrate that λ-meta dynamics simulations can recover the accurate potential of mean for ...[more]

PMID: 23678385

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?-Meta Dynamics Approach To Compute Absolute Solvation Free Energy.

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<i>λ</i>-Meta Dynamics Approach To Compute Absolute Solvation Free Energy.

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