Barrier crossing of semiflexible polymers
Barrier crossing of semiflexible polymers
复制标题
半柔性聚合物的势垒穿越
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
J. Kierfeld
中科院分区：
文献类型：
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作者：
P. Kraikivski;R. Lipowsky;J. Kierfeld
研究了半柔性高分子在双势阱中的运动。我们计算的形状，能量和有效的扩散常数的扭结激发，特别是它们的依赖于弯曲刚度的半柔性聚合物。对于对称势，扭结运动是纯扩散的，而扭结运动在聚合物上存在驱动力的情况下变成定向的。我们确定的平均速度的半柔性聚合物的扭结动力学的基础上。Kramers逃逸势垒的过程是通过扭结-反扭结对的成核和扩散运动进行的，通过扭结-反扭结对的湮灭弛豫到直线构型。我们的研究结果适用于生物聚合物，如DNA和肌动蛋白丝或合成的聚电解质结构基板上的激活运动。
We consider the motion of semiflexible polymers in double-well potentials. We calculate shape, energy, and effective diffusion constant of kink excitations, and in particular their dependence on the bending rigidity of the semiflexible polymer. For symmetric potentials, the kink motion is purely diffusive, whereas kink motion becomes directed in the presence of a driving force on the polymer. We determine the average velocity of the semiflexible polymer based on the kink dynamics. The Kramers escape over the potential barriers proceeds by nucleation and diffusive motion of kink-antikink pairs, the relaxation to the straight configuration by annihilation of kink-antikink pairs. Our results apply to the activated motion of biopolymers such as DNA and actin filaments or synthetic polyelectrolytes on structured substrates.