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arXiv · 0902.0302

Bottom-up derivation of an effective thermostat for united atoms simulations of water

Anders Eriksson·Martin Nilsson Jacobi·Johan Nystrom·Kolbjorn Tunstrom
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Abstract

In this article we derive the effective pairwise interactions in a Langevin type united atoms model of water. The interactions are determined from the trajectories of a detailed molecular dynamics simulation of simple point charge water. A standard method is used for estimating the conservative interaction, whereas a new "bottom-up" method is used to determine the effective dissipative and stochastic interactions. We demonstrate that, when compared to the standard united atoms model, the transport properties of the coarse-grained model is significantly improved by the introduction of the derived dissipative and stochastic interactions. The results are compared to a previous study, where a "top-down" approach was used to obtain transport properties consistent with those of the simple point charge water model.

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Anders Eriksson, Martin Nilsson Jacobi, Johan Nystrom, Kolbjorn Tunstrom. 2009-02-02. Bottom-up derivation of an effective thermostat for united atoms simulations of water. https://doi.org/10.1063/1.3119922

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