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arXiv · 1111.3231

Breakdown of the Kratky-Porod Wormlike Chain Model for Semiflexible Polymers in Two Dimensions

Hsiao-Ping Hsu·Wolfgang Paul·Kurt Binder
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Abstract

By large-scale Monte Carlo simulations of semiflexible polymers in $d=2$ dimensions the applicability of the Kratky-Porod model is tested. This model is widely used as "standard model" for describing conformations and force versus extension curves of stiff polymers. It is shown that semiflexible polymers in $d=2$ show a crossover from hard rods to self-avoiding walks, the intermediate Gaussian regime (implied by the Kratky-Porod model) is completely absent. Hence the latter can also describe force versus extension curves only if the contour length is only a few times larger than the persistence length. Consequences for experiments on biopolymers at interfaces are briefly discussed.

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Hsiao-Ping Hsu, Wolfgang Paul, Kurt Binder. 2011-11-14. Breakdown of the Kratky-Porod Wormlike Chain Model for Semiflexible Polymers in Two Dimensions. https://doi.org/10.1209/0295-5075%2F95%2F68004

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