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Publication Citation: Impact of surface roughness on diffusion of confined fluids

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Author(s): William P. Krekelberg; Vincent K. Shen; Jeffrey R. Errington; Thomas M. Truskett;
Title: Impact of surface roughness on diffusion of confined fluids
Published: October 17, 2011
Abstract: Using event-driven molecular dynamics simulations, we quantify how the self diffusivity of confined hard-sphere fluids depends on the nature of the confining boundaries. We explore systems with featureless confining boundaries that treat particle-boundary collisions in different ways and also various types of physically (i.e., geometrically) rough boundaries. We show that, for moderately dense fluids, the ratio of the self diffusivity of a rough wall system to that of an appropriate smooth-wall reference system is a linear function of the reciprocal wall separation, with the slope depending on the nature of the roughness. We also discuss some simple practical ways to use this information to predict confined hard-sphere fluid behavior in different rough-wall systems.
Citation: Journal of Chemical Physics
Volume: 135
Research Areas: Molecular Dynamics, Thin-Films, Surfaces, Materials Properties
PDF version: PDF Document Click here to retrieve PDF version of paper (1MB)