Bell Ian H
Applied Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, CO 80305
Proc Natl Acad Sci U S A. 2019 Mar 5;116(10):4070-4079. doi: 10.1073/pnas.1815943116. Epub 2019 Feb 15.
This work investigates the link between residual entropy and viscosity based on wide-ranging, highly accurate experimental and simulation data. This link was originally postulated by Rosenfeld in 1977 [Rosenfeld Y (1977) 15:2545-2549], and it is shown that this scaling results in an approximately monovariate relationship between residual entropy and reduced viscosity for a wide range of molecular fluids [argon, methane, [Formula: see text], [Formula: see text], refrigerant R-134a (1,1,1,2-tetrafluoroethane), refrigerant R-125 (pentafluoroethane), methanol, and water] and a range of model potentials (hard sphere, inverse power, Lennard-Jones, and Weeks-Chandler-Andersen). While the proposed "universal" correlation of Rosenfeld is shown to be far from universal, when used with the appropriate density scaling for molecular fluids, the viscosity of nonassociating molecular fluids can be mapped onto the model potentials. This mapping results in a length scale that is proportional to the cube root of experimentally measurable liquid volume values.
这项工作基于广泛、高度精确的实验和模拟数据，研究了残余熵与粘度之间的联系。这种联系最初由罗森菲尔德于1977年提出[罗森菲尔德Y（1977年）15:2545 - 2549]，结果表明，对于多种分子流体[氩气、甲烷、[化学式：见原文]、[化学式：见原文]、制冷剂R - 134a（1,1,1,2 - 四氟乙烷）、制冷剂R - 125（五氟乙烷）、甲醇和水]以及一系列模型势（硬球、逆幂、 Lennard - Jones和Weeks - Chandler - Andersen），这种标度关系在残余熵和折合粘度之间产生了近似单变量关系。虽然罗森菲尔德提出的“通用”关联远非通用，但当与分子流体的适当密度标度一起使用时，非缔合分子流体的粘度可以映射到模型势上。这种映射产生了一个与实验可测量的液体体积值的立方根成比例的长度尺度。
