Theory and Simulation of Complex Liquids, Solutions, Interfaces, and Nucleation Processes

该建议涉及复杂的液体和溶液，在均相和界面相互作用至关重要的情况下。长期目标是获得微观的系统，是具有根本性和实际重要性的理解。这是通过将第一原理统计力学分析与现代计算机模拟方法相结合来实现的。目前的主要研究内容如下：（1）水异常的成因及相关问题。水的重要性显而易见，但在分子水平上对它不同寻常的物理性质还没有很好的了解。我们工作的目标是直接将水的异常与局部分子排列联系起来。(2)不均匀冰成核冰成核作用在许多环境和生物系统中非常重要。我们的目标是确定一个好的冰核的特性，重点是对冰云形成至关重要的大气气溶胶粒子。(3)从溶液中结晶成核和生长。晶体在溶液中的成核和生长在许多物理过程中是重要的。我们的重点是了解成核机制，确定晶体诞生的早期阶段。(4)水溶液的微观不均匀性。一些两亲性小分子如醇的水溶液可以表现出与溶质聚集相关的显著行为。 我们正在使用大规模模拟来更清楚地了解这些聚集体的物理性质。(5)室温离子液体。在室温下以液体形式存在的离子化合物具有理论意义，并且作为具有特殊性质的溶剂正在工业上应用。我们的重点是了解有助于这些离子液体的熔点，结构和动力学的重要分子特征。(6)水和离子溶液在纳米孔中的吸附和传输。本项目的目的是研究水和离子溶液在不均匀纳米孔中的吸附、结构和传输。这样的系统具有从生物通道中的运输和选择性到纳米级流体导管和存储装置的发展的相关性。

This proposal is concerned with complex liquids and solutions, both in homogeneous phases and in situations where interfacial interactions are of crucial importance. The long-term objective is to gain a microscopic understanding of systems that are of both fundamental and practical importance. This is achieved by combining first principles statistical mechanical analyses with modern computer simulation methods. Principal areas of current research are as follows: (1) The Origin of Water's Anomalies and Related Questions. Water is of obvious importance, yet its unusual physical properties are not well understood at the molecular level. The objective of our work is to directly relate water's anomalies to local molecular arrangements. (2) Heterogeneous Ice Nucleation. Ice nucleation is very important in many environmental and biological systems. Our aim is to determine the characteristics of a good ice nucleus, with emphasis on atmospheric aerosol particles that are critical to ice cloud formation. (3) Crystal Nucleation and Growth from Solution. The nucleation and growth of crystals in solution is important in many physical processes. Our focus is to understand the nucleation mechanisms that determine the early stages of crystal birth. (4) Microheterogeneity in Aqueous Solutions. Aqueous solutions of some small amphiphilic molecules such as alcohols can exhibit remarkable behaviour associated with solute aggregation. We are using large-scale simulations to get a clearer picture of the physical nature of these aggregates. (5) Room Temperature Ionic Liquids. Ionic compounds that exist as liquids at room temperature are of theoretical interest, and are finding industrial application as solvents with special properties. Our focus is on understanding the important molecular features that contribute to the melting point, structure, and dynamics of these ionic liquid. (6) Adsorption and Transport of Water and Ionic Solutions in Nanopores. The objective of this project is to investigate adsorption, structure, and transport of water and ionic solutions in inhomogeneous nanopores. Such systems have relevance ranging from transport and selectivity in biological channels to the development of nanoscale fluid conduits and storage devices.