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arXiv · 1212.0339

A model for the dynamics of extensible semiflexible polymers

Gerard T. Barkema·J. M. J. van Leeuwen
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Abstract

We present a model for semiflexible polymers in Hamiltonian formulation which interpolates between a Rouse chain and worm-like chain. Both models are realized as limits for the parameters. The model parameters can also be chosen to match the experimental force-extension curve for double-stranded DNA. Near the ground state of the Hamiltonian, the eigenvalues for the longitudinal (stretching) and the transversal (bending) modes of a chain with N springs, indexed by p, scale as lambda_lp ~ (p/N)^2 and lambda_tp ~ p^2(p-1)^2/N^4 respectively for small p. We also show that the associated decay times tau_p ~ (N/p)^4 will not be observed if they exceed the orientational time scale tau_r ~ N^3 for an equally-long rigid rod, as the driven decay is then washed out by diffusive motion.

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Gerard T. Barkema, J. M. J. van Leeuwen. 2012-12-03. A model for the dynamics of extensible semiflexible polymers. https://doi.org/10.1088/1742-5468%2F2012%2F12%2Fp12019

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