https://doi.org/10.1140/epje/i2005-10023-9
Original Article
Different pathways in mechanical unfolding/folding cycle of a single semiflexible polymer
1
Department of Physics, Graduate School of Sciences, Kyoto University, 606-8502, Kyoto, Japan
2
Yukawa Institute for Theoretical Physics, Kyoto University, 606-8502, Kyoto, Japan
* e-mail: yoshinaga@scphys.kyoto-u.ac.jp
Received:
8
February
2005
Accepted:
16
June
2005
Published online:
23
August
2005
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.
PACS: 36.20.-r Macromolecules and polymer molecules – / 87.15.La Mechanical properties – / 05.70.Fh Phase transitions: general studies –
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2005