发表机构
School of Science, Civil Aviation Flight University of China（中国民用航空飞行大学理学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过分子动力学模拟，在400-800 K温度范围内系统检验了斯托克斯-爱因斯坦关系及其两种变体在离子液体中的有效性，发现变体不可靠，失效源于强静电相互作用导致的离子关联。
AI 中文摘要
离子液体（ILs）即使在室温以上也表现出过冷液体的行为，而斯托克斯-爱因斯坦（SE）关系通常被认为在离子液体中如同在过冷液体中一样不成立。然而，这一结论通常是基于SE关系的某些变体得出的。在本工作中，我们通过在400-800 K温度范围内对粗粒化离子液体进行分子动力学模拟，系统地研究了斯托克斯-爱因斯坦关系在离子液体中的有效性。我们检验了原始的SE公式以及两种常用的变体，以评估其适用性和一致性。这三种公式产生了明显不同的结果，表明这两种变体不能可靠地替代原始的SE关系。这种不一致性表明斯托克斯定律中的r随条件变化。这种失效源于强静电相互作用引入的离子关联。该命题通过模拟得到了进一步证实。
英文摘要
Ionic liquids (ILs) exhibit supercooled liquids behavior even above room temperature and the Stokes-Einstein (SE) relation is often considered to be invalid in ILs as that in supercooled liquids. However, the conclusion is usually drawn based on some variants of SE relation. In this work, we have systematically investigated the validity of the Stokes-Einstein relation in ILs by performing molecular dynamics simulations of coarse-grained IL within the temperature range of 400-800 K. Both the original SE formulation, and two commonly employed variants, were examined to assess their applicability and consistency. These three formulas yield distinctly different results, indicating that the two variants are not reliable substitutes for the original SE relation. The inconsistency suggests the fact that the r in Stokes law varies with conditions. The breakdown arises from the ion correlations introduced by the strong electrostatic interactions. This proposition is further confirmed by simulations.
