Cacciuto Angelo, Luijten Erik
Department of Materials Science and Engineering and Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Nano Lett. 2006 May;6(5):901-5. doi: 10.1021/nl052351n.
We compute the free energy of confinement for a flexible self-avoiding polymer inside a spherical cavity. Accurate numerical results allow us to arbitrate between three competing scaling predictions. For moderate confinement, the free energy exhibits a power-law dependence on cavity size that is different from what is observed for planar and cylindrical confinement. At high monomer concentrations, crossover to a different scaling regime is observed, consistent with the screening of the excluded-volume interactions. We demonstrate how our findings lead to a revised prediction for the escape time of a polymer from a spherical confinement.
我们计算了球形腔内柔性自回避聚合物的受限自由能。精确的数值结果使我们能够在三种相互竞争的标度预测之间做出判断。对于适度受限的情况,自由能对腔尺寸呈现幂律依赖关系,这与平面和圆柱受限情况下观察到的情况不同。在高单体浓度下,观察到向不同标度区域的转变,这与排除体积相互作用的屏蔽一致。我们展示了我们的发现如何导致对聚合物从球形受限中逃逸时间的修正预测。