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arXiv · 1608.07250

Tube Concept for Entangled Stiff Fibers Predicts Their Dynamics in Space and Time

Sebastian Leitmann·Felix Höfling·Thomas Franosch
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Abstract

We study dynamically crowded solutions of stiff fibers deep in the semidilute regime, where the motion of a single constituent becomes increasingly confined to a narrow tube. The spatiotemporal dynamics for wave numbers resolving the motion in the confining tube becomes accessible in Brownian dynamics simulations upon employing a geometry-adapted neighbor list. We demonstrate that in such crowded environments the intermediate scattering function, characterizing the motion in space and time, can be predicted quantitatively by simulating a single freely diffusing phantom needle only, yet with very unusual diffusion coefficients.

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Sebastian Leitmann, Felix Höfling, Thomas Franosch. 2016-08-25. Tube Concept for Entangled Stiff Fibers Predicts Their Dynamics in Space and Time. https://doi.org/10.1103/physrevlett.117.097801

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