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arXiv · 1111.0637

Friction contribution to water-bond breakage kinetics

Yann von Hansen·Felix Sedlmeier·Michael Hinczewski·Roland R. Netz
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Abstract

Based on the trajectories of the separation between water molecule pairs from MD simulations, we investigate the bond breakage dynamics in bulk water. From the spectrum of mean first-passage times, the Fokker-Planck equation allows us to derive the diffusivity profile along the separation coordinate and thus to unambiguously disentangle the effects of free-energy and local friction on the separation kinetics. For tightly coordinated water the friction is six times higher than in bulk, which can be interpreted in terms of a dominant reaction path that involves additional orthogonal coordinates.

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Yann von Hansen, Felix Sedlmeier, Michael Hinczewski, Roland R. Netz. 2011-11-02. Friction contribution to water-bond breakage kinetics. https://doi.org/10.1103/physreve.84.051501

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