Ultrafast Studies of Chemical Reactions in Simple Liquids

Charles Harris教授获理论与计算化学计划资助，研究溶剂对多原子单分子分解反应动力学的影响。他计划系统地研究包括过渡金属羰基在内的多种多原子分子在液态氙、氪和其他简单超临界溶剂（如一氧化碳和二氧化碳）中的皮秒和飞秒单分子解离反应。实验部分研究的主要重点将是确定溶剂密度和温度对与液态反应相关的各个步骤的定量影响。此外，还将进行理论研究，包括利用分子动力学和广义朗之万动力学模拟反应。大多数具有实际意义的化学反应都是在溶液中进行的。众所周知，在溶液中发生的反应受反应物质与溶剂分子的相互作用的影响，这种相互作用倾向于将反应物分子封闭在溶剂笼中。然而，对溶剂对化学反应的影响的理论认识还不是很清楚。哈里斯教授正在进行的研究将有助于阐明溶剂分子影响溶液中化学反应的机制，并将导致改进的理论，以提高我们对这一重要现象的理解。

Professor Charles Harris is supported by a grant from the Theoretical and Computational Chemistry Program to study solvent effects on reaction dynamics of polyatomic unimolecular decomposition reactions. He plans to systematically investigate the picosecond and femtosecond unimolecular dissociation reactions of a variety of polyatomic molecules including transition metal carbonyls in liquid xenon, krypton and other simple supercritical solvents such as carbon monoxide and carbon dioxide. The primary focus of the experimental part of the research will be to determine the quantitative effect of the solvent density and temperature on the individual steps associated with the liquid state reactions. In addition, theoretical studies will be pursued which will include simulating the reactions using molecular dynamics and generalized Langevin dynamics. %%% Most chemical reactions of practical importance take place in solution. It is known that the reactions which occur in solution are influenced by the interaction of the reacting species with the solvent molecules which tend to enclose the reactant molecules in solvent cages. Nevertheless, the theoretical understanding of the effects of solvent on a chemical reaction are not well understood. The research being performed by Professor Harris will help to elucidate the mechanism by which solvent molecules influence chemical reactions in solution, and will lead to improved theories for improving our understanding of this important phenomenon.