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Different pathways in mechanical unfolding/folding cycle of a single semiflexible polymer

Natsuhiko Yoshinaga·Kenichi Yoshikawa·Takao Ohta
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Abstract

Kinetics of conformational change of a semiflexible polymer under mechanical external field were investigated with Langevin dynamics simulations. It is found that a semiflexible polymer exhibits large hysteresis in mechanical folding/unfolding cycle even with a slow operation, whereas in a flexible polymer, the hysteresis almost disappears at a sufficiently slow operation. This suggests that the essential features of the structural transition of a semiflexible polymer should be interpreted at least on a two-dimensional phase space. The appearance of such large hysteresis is discussed in relation to different pathways in the loading and unloading processes. By using a minimal two-variable model, the hysteresis loop is described in terms of different pathways on the transition between two stable states.

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Natsuhiko Yoshinaga, Kenichi Yoshikawa, Takao Ohta. 2005-11-02. Different pathways in mechanical unfolding/folding cycle of a single semiflexible polymer. https://doi.org/10.1140/epje%2Fi2005-10023-9

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