Yuan Qi-Lu, Xu Xiaolei, Douglas Jack F, Xu Wen-Sheng
State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, P. R. China.
J Phys Chem B. 2024 Nov 7;128(44):10999-11021. doi: 10.1021/acs.jpcb.4c04806. Epub 2024 Oct 23.
We assess the validity of a range of models of glass formation based on molecular dynamics simulation results of the Kob-Andersen (KA) model system under a wide range of constant volume and constant pressure conditions. These models include the Adam-Gibbs model emphasizing configurational entropy, the string model emphasizing collective particle exchange motion, the shoving model emphasizing material elasticity, the localization model emphasizing dynamical free volume, and parabolic models based on the ideas of dynamic facilitation and, alternatively, the hypothesis that glass formation involves an avoided critical point. We demonstrate that these seemingly disparate models all provide a reasonable description of structural relaxation and diffusion data for the KA model system under all simulation conditions considered. Hence, the present study points to some unity in our understanding of the relationship between leading models of glass formation, supporting inferences drawn from previous studies of polymeric glass-forming liquids.
我们基于Kob-Andersen（KA）模型系统在广泛的恒容和恒压条件下的分子动力学模拟结果，评估了一系列玻璃形成模型的有效性。这些模型包括强调构型熵的Adam-Gibbs模型、强调集体粒子交换运动的弦模型、强调材料弹性的推挤模型、强调动态自由体积的局域化模型，以及基于动态促进思想和玻璃形成涉及避免临界点假设的抛物线模型。我们证明，在所有考虑的模拟条件下，这些看似不同的模型都能对KA模型系统的结构弛豫和扩散数据提供合理的描述。因此，本研究表明我们对玻璃形成主要模型之间关系的理解存在某种统一性，支持了先前对聚合物玻璃形成液体研究得出的推论。
