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arXiv · 0803.4140

Stretching helical nano-springs at finite temperature

Hirofumi Wada·Roland R. Netz
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Abstract

Using dynamic simulations and analytic methods, we study the elastic response of a helical filament subject to uniaxial tension over a wide range of bend and twist persistence length. A low-pitch helix at low temperatures exhibits a stretching instability and the force-extension curve consists of a sequence of spikes. At elevated temperature (i.e. small persistence lengths) the helix melts and a pronounced force plateau is obtained in the fixed-extension ensemble. The torque boundary condition significantly affects the resulting elastic properties.

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Hirofumi Wada, Roland R. Netz. 2008-03-28. Stretching helical nano-springs at finite temperature. https://doi.org/10.1209/0295-5075%2F77%2F68001

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