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arXiv · cond-mat/0310598

A new model for simulating colloidal dynamics

Vladimir Lobaskin·Burkhard Duenweg
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Abstract

We present a new hybrid lattice-Boltzmann and Langevin molecular dynamics scheme for simulating the dynamics of suspensions of spherical colloidal particles. The solvent is modeled on the level of the lattice-Boltzmann method while the molecular dynamics is done for the solute. The coupling between the two is implemented through a frictional force acting both on the solvent and on the solute, which depends on the relative velocity. A spherical colloidal particle is represented by interaction sites at its surface. We demonstrate that this scheme quantitatively reproduces the translational and rotational diffusion of a neutral spherical particle in a liquid and show preliminary results for a charged spherical particle. We argue that this method is especially advantageous in the case of charged colloids.

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Vladimir Lobaskin, Burkhard Duenweg. 2003-10-24. A new model for simulating colloidal dynamics. https://doi.org/10.1088/1367-2630%2F6%2F1%2F054

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