Caraglio Michele, Micheletti Cristian, Orlandini Enzo
Dipartimento di Fisica e Astronomia, Università di Padova and sezione CNISM, Via Marzolo 8, I-35131 Padova, Italy.
SISSA, International School for Advanced Studies, via Bonomea 265, I-34136 Trieste, Italy.
Polymers (Basel). 2017 Aug 1;9(8):327. doi: 10.3390/polym9080327.
By using Langevin dynamics simulations, we study how semiflexible rings that are topologically linked respond to mechanical stretching. We use both constant-force and constant-velocity pulling protocols and map out how the mechanical tension affects observables related to metric quantities such as the longitudinal extension or span, and topology-related ones such as the length of the linked portion. We find that the average extension of linked rings, once divided by that of a single equivalent ring, is nonmonotonic in the applied force. We show that this remarkable feature becomes more prominent as the link complexity is increased, and originates from the different stretching compliance of the linked portion and the rest of the rings' contour. By comparing the results of different pulling protocols, we also establish the best one for telling apart different types of links from their tensile response.
通过使用朗之万动力学模拟，我们研究了拓扑相连的半柔性环如何响应机械拉伸。我们采用恒力和恒速拉伸协议，并描绘出机械张力如何影响与度量量相关的可观测量，如纵向伸长或跨度，以及与拓扑相关的可观测量，如相连部分的长度。我们发现，相连环的平均伸长量一旦除以单个等效环的平均伸长量，在施加的力中是非单调的。我们表明，随着连接复杂性的增加，这一显著特征变得更加突出，并且源于相连部分和环轮廓其余部分不同的拉伸顺应性。通过比较不同拉伸协议的结果，我们还确定了从拉伸响应中区分不同类型连接的最佳方法。
