Freiburger Institut für Interaktive Materialien und Bioinspirierte Technologien, Georges-Köhler-Allee 105, 79110, Freiburg, Germany.
Physikalisches Institut, Universität Freiburg, Herrmann-Herder-Straße 3, 79104, Freiburg, Germany.
Chemphyschem. 2022 Oct 6;23(19):e202200237. doi: 10.1002/cphc.202200237. Epub 2022 Aug 3.
Bond rupture under the action of external forces is usually induced by temperature fluctuations, where the key quantity is the force dependent barrier that needs to be overcome. Using analytic potentials we find that these barriers are fully determined by the dissociation energy and the maximal force the potential can withstand. The barrier shows a simple dependence on these two quantities that allows for a re-interpretation of the Eyring-Zhurkov-Bell length and the expressions in theories going beyond that. It is shown that solely elastic environments do not change this barrier in contrast to the predictions of constraint geometry simulate external force (COGEF) strategies. The findings are confirmed by explicit calculations of bond rupture in a polydimethylsiloxane model.
在外部力的作用下，键的断裂通常是由温度波动引起的，其中关键量是需要克服的力相关势垒。使用解析势，我们发现这些势垒完全由离解能和势所能承受的最大力决定。势垒对这两个量表现出简单的依赖性，这使得对 Eyring-Zhurkov-Bell 长度以及超越该理论的表达式进行重新解释成为可能。结果表明，与约束几何模拟外力 (COGEF) 策略的预测相反，仅弹性环境不会改变这种势垒。在聚二甲基硅氧烷模型中对键断裂的显式计算证实了这一发现。
