Two-phase stretching of molecular chains

@article{Savin2011TwophaseSO,
  title={Two-phase stretching of molecular chains},
  author={Alexander V. Savin and Irina P. Kikot and Mikhail A. Mazo and Alexey V. Onufriev},
  journal={Proceedings of the National Academy of Sciences},
  year={2011},
  volume={110},
  pages={2816 - 2821}
}
Although stretching of most polymer chains leads to rather featureless force-extension diagrams, some, notably DNA, exhibit nontrivial behavior with a distinct plateau region. Here, we propose a unified theory that connects force-extension characteristics of the polymer chain with the convexity properties of the extension energy profile of its individual monomer subunits. Namely, if the effective monomer deformation energy as a function of its extension has a nonconvex (concave up) region, the… 

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