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arXiv · 0808.0450

Effective Perrin theory for the anisotropic diffusion of a strongly hindered rod

Tobias Munk·Felix Höfling·Erwin Frey·Thomas Franosch
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Abstract

Slender rods in concentrated suspensions constitute strongly interacting systems with rich dynamics: transport slows down drastically and the anisotropy of the motion becomes arbitrarily large. We develop a mesoscopic description of the dynamics down to the length scale of the interparticle distance. Our theory is based on the exact solution of the Smoluchowski-Perrin equation; it is in quantitative agreement with extensive Brownian dynamics simulations in the dense regime. In particular, we show that the tube confinement is characterised by a power law decay of the intermediate scattering function with exponent 1/2.

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Tobias Munk, Felix Höfling, Erwin Frey, Thomas Franosch. 2009-01-13. Effective Perrin theory for the anisotropic diffusion of a strongly hindered rod. https://doi.org/10.1209/0295-5075/85/30003

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