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arXiv · 1101.2196

Phase diagram and effective shape of semi-flexible colloidal rods and biopolymers

Matthew Dennison·Marjolein Dijkstra·Rene van Roij
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Abstract

We study suspensions of semi-flexible colloidal rods and biopolymers using an Onsager-type second-virial functional for a segmented-chain model. For suspensions of thin and thick fd virus particles we calculate phase diagrams in quantitative agreement with experimental observations, and we find their effective state-point dependent shape to be much shorter and thicker than the actual shape. We also calculate the stretching of worm-like micelles in a host fd virus solution, again finding agreement with experiments. For both systems, our results show that the fd virus stiffness can play a key role in system behavior.

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Matthew Dennison, Marjolein Dijkstra, Rene van Roij. 2011-01-11. Phase diagram and effective shape of semi-flexible colloidal rods and biopolymers. https://doi.org/10.1103/physrevlett.106.208302

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