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arXiv · 0808.3205

Compression and stretching of a self-avoiding chain in cylindrical nanopores

Suckjoon Jun·D. Thirumalai·Bae-Yeun Ha
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Abstract

Force-induced deformations of a self-avoiding chain confined inside a cylindrical cavity, with diameter $D$, are probed using molecular dynamics simulations, scaling analysis, and analytical calculations. We obtain and confirm a simple scaling relation $-f \cdot D \sim R^{-9/4}$ in the strong-compression regime, while for weak deformations we find $f \cdot D = -A(R/R_0) + B (R/R_0)^{-2}$, where $A$ and $B$ are constants, $f$ the external force, and $R$ the chain extension (with $R_0$ its unperturbed value). For a strong stretch, we present a universal, analytical force-extension relation. Our results can be used to analyze the behavior of biomolecules in confinement.

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Suckjoon Jun, D. Thirumalai, Bae-Yeun Ha. 2008-08-23. Compression and stretching of a self-avoiding chain in cylindrical nanopores. https://doi.org/10.1103/physrevlett.101.138101

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