Reaction Dynamics of Vibrationally Excited Molecules in Gases and Liquids

气体和液体中振动激发分子的反应动力学

• 批准号: 1321931
• 负责人: Martin Zanni
• 金额: $ 50.96万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-15 至 2017-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1321931&HistoricalAwards=false
• 关键词: Reaction; Dynamics; Vibrationally; Excited; Molecules

This project is a unified study of reactions in liquids and gases with the goal of comparing the influence of vibrational excitation on bimolecular reactions in the two settings and of understanding the role played by the surroundings. In gases, bimolecular reactions can be promoted and controlled using laser pulses to generate a reactive radical, to excite a reactant vibrationally, and to detect the reaction products. The same conceptual approach, using different technology, will be applied in liquids. Gas-phase studies rely on relatively high spectral resolution lasers to prepare and probe individual quantum states of the reactants and products. Because of the frequent encounters in liquids, studies in solution need short time resolution, with the consequence that the spectral resolution of the laser pulses is poorer. Nonetheless, it is possible to excite and probe individual vibrations in liquids by a judicious choice of time and spectral resolution in the excitation and interrogation steps. This project will use bromine in vibrational-mode selective single collision reactions and compare gas-phase reactions with those in solution. The high time resolution in the solution-phase experiments will allow the direct observation of the evolution of a photolytically generated bromine atom as it forms complexes and reacts with vibrationally excited solvent molecules. Single collision studies of the same reactions in a molecular beam will provide a point of comparison by observing the influence of vibrational excitation without the complication of the surrounding solvent. The fundamental science in this project will provide valuable experience and skills to graduate students, as well as opportunities designed to integrate research, teaching, and learning at the University of Wisconsin/Madison. The principal investigator will participate in education and policy related activities, and reach out to beginning scientists about the research enterprise.

该项目是对液体和气体中反应的统一研究，目的是比较两种环境中振动激发对双分子反应的影响，并了解环境所起的作用。在气体中，可以使用激光脉冲来促进和控制双分子反应，以产生反应性自由基，以振动方式激发反应物，并检测反应产物。同样的概念方法，使用不同的技术，将适用于液体。气相研究依赖于相对高的光谱分辨率激光来制备和探测反应物和产物的各个量子态。由于在液体中的频繁遭遇，溶液中的研究需要短时间分辨率，结果是激光脉冲的光谱分辨率较差。尽管如此，通过在激发和询问步骤中明智地选择时间和光谱分辨率，可以激发和探测液体中的个体振动。 该项目将在振动模式选择性单碰撞反应中使用溴，并将气相反应与溶液中的反应进行比较。在溶液相实验中的高时间分辨率将允许直接观察光解产生的溴原子的演变，因为它形成复合物并与振动激发的溶剂分子反应。在分子束中对相同反应的单次碰撞研究将提供一个比较点，通过观察振动激发的影响，而不受周围溶剂的影响。 在这个项目的基础科学将提供宝贵的经验和技能，研究生，以及旨在整合研究，教学和学习的机会在威斯康星州/麦迪逊大学。首席研究员将参与教育和政策相关活动，并接触有关研究企业的新科学家。