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arXiv · 1903.01703

Coarse-graining strategy for modeling effective, highly diffusive fluids with reduced polydispersity: A dynamical study

Thomas Heinemann·YounJoon Jung
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Abstract

We present a coarse-graining strategy for reducing the number of particle species in mixtures to achieve a simpler system with higher diffusion while preserving the total particle number and characteristic dynamic features. As a system of application, we chose the bidisperse Lennard-Jones-like mixture discovered by Kob and Andersen [Phys. Rev. Lett. 73, 1376 (1994)] possessing a slow dynamics due to the fluid's multi-component character with its apparently unconventional choice for the pair potential of the type-A-type-B arrangement. We further established in a so-formed coarse-grained and temperature-independent monodisperse system an equilibrium structure with a radial distribution function resembling its mixture counterpart. This one-component system further possesses similar dynamic features like glass transition temperature and critical exponents while subjected to Newtonian mechanics. This strategy may finally lead to the manufacturing of new nanoparticle/colloidal fluids by experimentally modeling only the outcoming effective pair potential(s) and no other macroscopic quantity.

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Thomas Heinemann, YounJoon Jung. 2019-03-05. Coarse-graining strategy for modeling effective, highly diffusive fluids with reduced polydispersity: A dynamical study. https://doi.org/10.1063/5.0009156

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