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 Oct 10;128(40):9889-9904. doi: 10.1021/acs.jpcb.4c04721. Epub 2024 Oct 1.
We systematically study glass formation in the well-known Kob-Andersen model over a wide range of densities and pressures as a basis for judging the "universality" of glass formation through a comparison to a recent systematic study of model polymeric glass-forming liquids. Our purpose is to establish general characteristics of glass formation, to identify new relations, and to discern which properties of glass-forming liquids are material-specific and which are "universal." To this end, we analyze a number of characteristic properties of glass formation, such as the structural relaxation time, self-diffusion coefficient, viscosity, characteristic temperatures, and fragility. We also consider a suite of properties presumably related to dynamic heterogeneity in an attempt to better understand its relation to structural relaxation. We demonstrate that the glassy dynamics in the Kob-Andersen model exhibit many of the essential trends observed in polymeric glass-forming liquids, pointing to a remarkable "universality" of many aspects of glass formation.
我们系统地研究了著名的科布-安德森模型在广泛的密度和压力范围内的玻璃形成情况，以此作为通过与最近对模型聚合物玻璃形成液体的系统研究进行比较来判断玻璃形成“普遍性”的基础。我们的目的是确立玻璃形成的一般特征，识别新的关系，并辨别玻璃形成液体的哪些性质是材料特有的，哪些是“普遍的”。为此，我们分析了玻璃形成的一些特征性质，如结构弛豫时间、自扩散系数、粘度、特征温度和脆性。我们还考虑了一系列可能与动态非均匀性相关的性质，试图更好地理解其与结构弛豫的关系。我们证明，科布-安德森模型中的玻璃态动力学表现出许多在聚合物玻璃形成液体中观察到的基本趋势，这表明玻璃形成的许多方面具有显著的“普遍性”。
