TY - JOUR
T1 - A temperature accelerated method for sampling free energy and determining reaction pathways in rare events simulations
AU - Maragliano, Luca
AU - Vanden-Eijnden, Eric
N1 - Funding Information:
We are grateful to Giovanni Ciccotti and Tommy Miller for many useful discussions and suggestions. The idea to use (9) to seamlessly apply TPS in collective variables is part of a joint project with Tommy Miller. This work is partially supported by NSF grants DMS02-09959 and DMS02-39625, and by ONR grant N00014-04-1-0565.
PY - 2006/7/26
Y1 - 2006/7/26
N2 - A method for sampling efficiently the free energy landscape of a complex system with respect to some given collective variables is proposed. Inspired by metadynamics [A. Laio, M. Parrinello, Proc. Nat. Acad. Sci. USA 99 (2002) 12562], we introduce an extended system where the collective variables are treated as dynamical ones and show that this allows to sample the free energy landscape of these variables directly. The sampling is accelerated by using an artificially high temperature for the collective variables. The validity of the method is established using general results for systems with multiple time-scales, and its numerical efficiency is also discussed via error analysis. We also show how the method can be modified in order to sample the reactive pathways in free energy space, and thereby analyze the mechanism of a reaction. Finally, we discuss how the method can be generalized and used as an alternative to the Kirkwood generalized thermodynamic integration approach for the calculation of free energy differences.
AB - A method for sampling efficiently the free energy landscape of a complex system with respect to some given collective variables is proposed. Inspired by metadynamics [A. Laio, M. Parrinello, Proc. Nat. Acad. Sci. USA 99 (2002) 12562], we introduce an extended system where the collective variables are treated as dynamical ones and show that this allows to sample the free energy landscape of these variables directly. The sampling is accelerated by using an artificially high temperature for the collective variables. The validity of the method is established using general results for systems with multiple time-scales, and its numerical efficiency is also discussed via error analysis. We also show how the method can be modified in order to sample the reactive pathways in free energy space, and thereby analyze the mechanism of a reaction. Finally, we discuss how the method can be generalized and used as an alternative to the Kirkwood generalized thermodynamic integration approach for the calculation of free energy differences.
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U2 - 10.1016/j.cplett.2006.05.062
DO - 10.1016/j.cplett.2006.05.062
M3 - Article
AN - SCOPUS:33745762636
SN - 0009-2614
VL - 426
SP - 168
EP - 175
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 1-3
ER -