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arXiv · 1706.10116

Dissipative particle dynamics: systematic parametrization using water-octanol partition coefficients

Richard L. Anderson·David J. Bray·Andrea S. Ferrante·Massimo G. Noro·Ian P. Stott·Patrick B. Warren
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Abstract

We present a systematic, top-down, thermodynamic parametrization scheme for dissipative particle dynamics (DPD) using water-octanol partition coefficients, supplemented by water-octanol phase equilibria and pure liquid phase density data. We demonstrate the feasibility of computing the required partition coefficients in DPD using brute-force simulation, within an adaptive semi-automatic staged optimization scheme. We test the methodology by fitting to experimental partition coefficient data for twenty one small molecules in five classes comprising alcohols and poly-alcohols, amines, ethers and simple aromatics, and alkanes (i.e. hexane). Finally, we illustrate the transferability of a subset of the determined parameters by calculating the critical micelle concentrations of selected alkyl ethoxylate surfactants, in good agreement with reported experimental values.

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Richard L. Anderson, David J. Bray, Andrea S. Ferrante, Massimo G. Noro, Ian P. Stott, Patrick B. Warren. 2017-06-30. Dissipative particle dynamics: systematic parametrization using water-octanol partition coefficients. https://doi.org/10.1063/1.4992111

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