Theoretical Studies of Molecular Interactions, Structure, Dynamics and Spectroscopy in Clusters and Condensed Matter

随着（超快）光谱学的最新进展，现在可以非常详细地观察分子系统和实时化学反应，人们对化学反应动力学和热力学的理论研究越来越感兴趣，因为它们可以预测、解释和指导实验。特别是，分子动力学技术可以在微观水平上模拟原子和分子的运动，为化学反应的机理和动力学提供宝贵的信息。这些研究是必不可少的，因为它们提供了由电子结构理论（量子化学）计算的势能面与化学动力学和热力学的实验测量之间的联系。在许多情况下，实验观察到的东西太复杂，没有理论的帮助就无法解释和理解。此外，与实验的联系对于评估计算机模拟和理论模型的可靠性至关重要，而这反过来又可以用来提高我们对化学的基本理解。**提出了针对真实计算机模拟的工具开发的新方向，包括改进分子相互作用的描述以及在动态模拟中包含量子核效应和可能的非绝热效应。大多数应用将集中在簇上，它是原子或分子的聚集体，在气相和冷凝（液体）相之间架起桥梁。团簇可以用作选择性微溶剂化的工具，或者它们可以是一类具有独特性质的独特材料。我们将重点研究(1)团簇纳米材料的结构和反应，(2)离子和盐种子溶剂团簇的光化学，以及(3)复杂离子和盐的团簇和大块溶剂化。我们的理论研究将有助于解释和指导实验研究，并将有助于更深入地了解分子水平的化学，具有从纳米技术（如氢/能量存储，催化）到生物学（如蛋白质变性）的各种潜在应用。

With the recent advances in (ultrafast) spectroscopy, which now permit the observation of molecular systems in great detail and chemical reactions in real time, there is an ever increasing interest in theoretical studies of chemical reaction dynamics and thermodynamics, as they can predict, explain and guide experiments. In particular, molecular dynamics techniques allow the motion of atoms and molecules to be simulated at the microscopic level, providing invaluable information about the mechanism and kinetics of chemical reactions. These studies are essential since they provide a link between potential energy surfaces calculated by electronic structure theory (quantum chemistry) and experimental measurements of chemical dynamics and thermodynamics. In many instances, experimental observables are too convoluted to explain and understand without the help of theory. Furthermore, connection with experiment is crucial for assessing the reliability of computer simulations and theoretical models, which, in turn can be used to improve our fundamental understanding of chemistry.**New directions are proposed for the development of tools aimed at realistic computer simulations, which include an improved description of molecular interactions and the inclusion of quantum nuclear effects and possible nonadiabatic effects in dynamical simulations. Most applications will focus on clusters, which are aggregates of atoms or molecules which bridge the gap between the gas and condensed (liquid) phases. Clusters can be used as tools for selective microsolvation, or they can be a distinct class of materials with unique properties. We will study, in particular, (1) the structure and reactions of cluster nanomaterials, (2) the photochemistry of solvent clusters seeded by ions and salts, and (3) the cluster and bulk solvation of complex ions and salts. Our theoretical studies will help explain and guide experimental studies, and will contribute to a deeper molecular-level understanding of chemistry, with diverse potential applications from nanotechnology (e.g. hydrogen/energy storage, catalysis) to biology (e.g. protein denaturation).