论文标题
玻璃形成液体脆弱性的视角
A perspective on the fragility of glass-forming liquids
论文作者
论文摘要
我们讨论了在大气压力下的“脆弱性”的常规测量中的可能无关效应，这可能会掩盖真正的超级阿尔希尼乌斯放松速度的表征。我们首先考虑密度的作用，密度会随着恒定压力下的温度降低而增加，然后是高温动力学行为和相关激活能量表的潜在影响。这两个效应既涉及热力学参数，也涉及反映相邻分子之间特定键的“裸”活化能的强度。它们因系统而异，很可能与与玻璃形成相关的任何推定的集体行为几乎没有联系。我们通过完善脆弱性的定义并修改著名的天使情节来展示如何扩展这些效果。我们将此笔记献给了我们伟大而鼓舞人心的朋友奥斯丁·安杰尔（Austen Angell），并在这次致敬中的同事丹尼尔·基维尔森（Daniel Kivelson）死了。
We discuss possible extraneous effects entering in the conventional measures of "fragility" at atmospheric pressure that may obscure a characterization of the genuine super-Arrhenius slowdown of relaxation. We first consider the role of density, which increases with decreasing temperature at constant pressure, and then the potential influence of the high-temperature dynamical behavior and of the associated activation energy scale. These two effects involve both thermodynamic parameters and the strength of the "bare" activation energy reflecting the specific bonding between neighboring molecules. They vary from system to system with, most likely, little connection with any putative collective behavior associated with glass formation. We show how to scale these effects out by refining the definition of fragility and modifying the celebrated Angell plot. We dedicate this note to our great and so inspiring friend, Austen Angell, and associate in this tribute another dear colleague who died too soon, Daniel Kivelson.
