We study the role of quantum fluctuations of atomic nuclei in thermally activated, out-of-equilibrium processes . To this goal we introduce an extension of the Dominant Reaction Pathways (DRP) formalism, in which the quantum corrections to the classical  Langevin dynamics are rigorously taken into account to order hbar^2 . We apply our method to study the C 7_eq -> C 7_ax transition of alanine dipeptide. We find that quantum fluctuations significantly modify the reaction mechanism with respect to a classical calculation . For example, the energy difference which is overcome along the most probable pathway is reduced by as much as 50\%.
We study the role of quantum fluctuations of atomic nuclei in the real-time dynamics of non-equilibrium macro-molecular transitions . To this goal we introduce an extension of the Dominant Reaction Pathways (DRP) formalism, in which the quantum corrections to the classical overdamped Langevin dynamics are rigorously taken into account to second order in h-bar. We first illustrate our approach with a simple toy model and then we apply it to study the C7_{eq transition of alanine dipeptide. We find that the inclusion of quantum fluctuations can significantly modify the reaction mechanism . For example, the energy difference which is overcome along the most probable pathway is reduced by as much as 50\%.
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thermally activated, out-of-equilibrium processes
the real-time dynamics of non-equilibrium macro-molecular transitions
A
overdamped
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order hbar^2 . We apply our method
second order in h-bar. We first illustrate our approach with a simple toy model and then we apply it
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C 7_eq -> C 7_ax
C7_{eq
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quantum fluctuations
the inclusion of quantum fluctuations can
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with respect to a classical calculation