Developing a Molecularly Detailed Theoretical Framework for Predicting the Thermodynamic Properties of Ionic Liquids

离子液体（IL）是完全由络合离子组成的液体，其通常具有等于或低于室温的熔点，将它们与高温熔融盐（例如，NaCl）。阳离子和阴离子各自赋予IL不同的物理和化学性质，使得IL能够被定制以提供期望的性质。虽然人们最初对离子液体的兴趣集中在它们作为溶剂的用途上，但随着离子液体在催化、分离、传感器、太阳能电池、电池、热流体和润滑剂等领域的应用，这种兴趣已显着扩大。这些应用，结合可能的离子液体的数量估计是在数十亿美元，强调需要开发一个准确的工具来设计特定任务的离子液体。尽管增加了实验研究和物理性质的调查，它是目前无法预测的离子组合将导致一组所需的属性。到目前为止，在IL设计的有限进展主要是通过化学成分实验，导致经验化学相关的properties.尽管其明显的效用，IL的预测设计方法，基于深刻的物理理解的结构和相互作用的IL，不存在今天。这部分是因为IL及其与其他分子物种的混合物是非常复杂的系统，并且从模拟和理论的角度来看，特别是如果我们希望能够在缺乏实验数据的情况下预测IL特性，则存在特别困难的分子建模挑战。我们将通过发展一个以分子为基础的理论框架来研究离子液体的热力学性质，从而满足这一需求。开发的方法将类似于分子模拟研究中使用的模型，并将能够从化学组成预测IL属性，从而消除在估计给定的离子组合及其与分子物种的混合物的属性时的不确定性。除了使产品设计的离子液体及其混合物，拟议的方法将是一个关键组成部分，在设计的化学过程中涉及离子液体。

Abstract#1067642McCabe, Clare M.Vanderbilt UniversityIonic liquids (ILs) are liquids, comprised entirely of complex ions, that typically have melting points at or below room temperature, distinguishing them from high temperature molten salts (e.g., NaCl). The cations and anions each impart different physical and chemical properties to the IL enabling ILs to be tailored to provide desired properties. While initial interest in ILs focused on their use as solvents, it has since broadened dramatically with ILs finding applications from catalysis, separations, sensors, solar cells, batteries, thermal fluids and lubricants. These applications, combined with the number of possible ILs being estimated to be in the billions, underlines the need to develop an accurate tool to design task-specific ILs.Despite increased experimental studies and physical property investigations, it is currently not possible to predict which ion combinations will lead to a desired set of properties. The limited progress to date in IL design has been achieved primarily through experimentation in chemical composition leading to empirical heuristics relating chemistry to properties.Despite its obvious utility, a predictive design methodology for ILs, based upon a deep physical understanding of the structure and interactions within ILs, does not exist today. This is in part because ILs and their mixtures with other molecular species are exceptionally complex systems and present particularly difficult molecular modeling challenges, both from simulation and theory points of view, especially if we wish to be able to predict IL properties in the absence of experimental data. We will address this need through the development of a molecular-based theoretical framework with which to study the thermodynamic properties of ILs. The approach developed will be akin to the models used in molecular simulation studies and will enable the prediction of IL properties from the chemical composition, so eliminating empiricism in estimating the properties of a given combination of ions and their mixtures with molecular species. In addition to enabling product design for ILs and their mixtures, the proposed methodology will be a crucial component in the design of chemical processes involving ILs.