Fitting of viscosity: Distinguishing the temperature dependences predicted by various models of supercooled liquids
Fitting of viscosity: Distinguishing the temperature dependences predicted by various models of supercooled liquids
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DOI：
10.1103/physreve.53.751
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发表时间：
1996-01-01
影响因子：
2.4
通讯作者：
Kivelson, SA
中科院分区：
文献类型：
--
作者：
Kivelson, D;Tarjus, G;Kivelson, SA
为了评估各种竞争理论模型的适用性，我们研究了各种过冷液体的粘度 eta(T) 和 α 弛豫时间的温度依赖性。在高于玻璃化转变温度的整个温度范围内以及对于所研究的所有不同过冷液体，整体最佳拟合由表达式 Tln[eta(T)/eta(infinity)]=E(infinity) + BT*[(T* - T)/T*](8/3)Theta(T* - T) 给出，其中 Theta(T* - T) 是阶跃函数，对于 T < T* 为 1，对于 T > 为 0 T*，且T*通常大于熔点温度。我们的分析支持这样的观点，即在过冷液体的整个 T 范围特征中，所有过冷液体的弛豫背后存在一个单一的、与物种无关的、非分子的主导机制。
In an effort to assess the applicability of various competing theoretical models, we have examined the temperature dependence of the viscosity eta(T) and of the alpha-relaxation times of a wide variety of super-cooled liquids. The overall best fits over the entire temperature range above the glass-transition temperature and for all the diverse supercooled liquids investigated are given by the expression Tln[eta(T)/eta(infinity)]=E(infinity) + BT*[(T* - T)/T*](8/3)Theta(T* - T), where Theta(T* - T) is a step function that is 1 for T < T* and 0 for T > T*, and T* is usually greater than the melting point temperature. Our analysis supports the notion that there is a single dominant species-independent, nonmolecular mechanism underlying a relaxation for all supercooled liquids, throughout the entire T-range characteristic of supercooled liquids.