Screening properties of Gaussian electrolyte models, with application to dissipative particle dynamics

Patrick B. Warren; Andrey Vlasov; Lucian Anton; Andrew J. Masters

doi:10.1063/1.4807057

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arXiv · 1303.0891

Screening properties of Gaussian electrolyte models, with application to dissipative particle dynamics

Patrick B. Warren·Andrey Vlasov·Lucian Anton·Andrew J. Masters

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Abstract

We investigate the screening properties of Gaussian charge models of electrolyte solutions by analysing the asymptotic behaviour of the pair distribution functions. We use a combination of Monte-Carlo simulations with the hyper-netted chain integral equation closure, and the random phase approximation, to establish the conditions under which a screening length is well defined and the extent to which it matches the expected Debye length. For practical applications, for example in dissipative particle dynamics, we are able to summarise our results in succinct rules-of-thumb which can be used for mesoscale modeling of electrolyte solutions. We thereby establish a solid foundation for future work, such as the systematic incorporation of specific ion effects.

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Patrick B. Warren, Andrey Vlasov, Lucian Anton, Andrew J. Masters. 2013-03-04. Screening properties of Gaussian electrolyte models, with application to dissipative particle dynamics. https://doi.org/10.1063/1.4807057

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