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

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 such as 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.

Computational investigation of dynamical heterogeneity in ionic liquids based on the restricted primitive model

“…This makes it challenging to obtain the dynamic properties at low temperatures where slow dynamics arise. Reducing the number of charged particles by the coarse-graining procedure may not be sufficient to substantially enhance the simulation efficiency, although various approaches, both structural 11,15,16,33 and dynamical, 34 have been carried out.…”