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arXiv · 1909.06285

Linear Dimensions of Adsorbed Semiflexible Polymers: What can be learned about their persistence length?

Andrey Milchev·Kurt Binder
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Abstract

Conformations of partially or fully adsorbed semiflexible polymer chains are studied varying both contour length $L$, chain stiffness, $\kappa$, and the strength of the adsorption potential over a wide range. Molecular Dynamics simulations show that partially adsorbed chains (with "tails", surface attached "trains" and "loops") are not described by the Kratky-Porod wormlike chain model. The crossover of the persistence length from its three-dimensional value $(\ell_p)$ to the enhanced value in two dimensions $(2\ell_p)$ is analyzed, and excluded volume effects are identified for $L \gg \ell_p$. Consequences for the interpretation of experiments are suggested. We verify the prediction that the adsorption threshold scales as $\ell_p^{-1/3}$.

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Andrey Milchev, Kurt Binder. 2019-09-13. Linear Dimensions of Adsorbed Semiflexible Polymers: What can be learned about their persistence length?. https://doi.org/10.1103/physrevlett.123.128003

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