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Screening properties of four mesoscale smoothed charge models, with application to dissipative particle dynamics

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 نشر من قبل Patrick Warren
 تاريخ النشر 2014
  مجال البحث فيزياء
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We extend our previous study [J. Chem. Phys. 138, 204907 (2013)] to quantify the screening properties of four mesoscale smoothed charge models used in dissipative particle dynamics. Using a combination of the hypernetted chain integral equation closure and the random phase approximation, we identify regions where the models exhibit a real-valued screening length, and the extent to which this agrees with the Debye length in the physical system. We find that the second moment of the smoothed charge distribution is a good predictor of this behaviour. We are thus able to recommend a consistent set of parameters for the models.

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