Investigation of Aerosol Formation and Heterogeneous Chemistry on a Molecular Level: The Reactivity, Stability, and Photochemistry of Small Clusters of Atmospheric Interest

分子水平上气溶胶形成和多相化学的研究：大气中感兴趣的小团簇的反应性、稳定性和光化学

• 批准号: 8714095
• 负责人: A. Castleman
• 金额: $ 62.09万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-10-15 至 1991-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8714095&HistoricalAwards=false
• 关键词: Investigation; Aerosol; Formation; Heterogeneous; Chemistry

The formation and chemical role of aerosols is an important aspect of atmospheric chemistry that is still relatively poorly understood. Considerable knowledge and insight into the formation of aerosols, their subsequent growth, and the chemical transformations that occur within or that are catalyzed by aerosols can be gained through an investigation of gas-phase molecular clusters. Information on clusters is crucial for determining the stability of prenucleation embryos and formulating theories of gas-to-particle conversion. Clusters also provide a medium through which a detailed understanding of heterogeneous reactions, including the role of metal ions and photochemical processes on chemical conversions can be obtained on a molecular level. This research project involves an experimental study in three main areas which will serve to elucidate important aspects of the above mentioned processes. These include investigations of: (1) the kinetics of association (clustering) reactions and the subsequent reactions of clusters with atmospheric molecules; (2) the thermochemical properties of clusters; and (3) photochemical reactions within clusters, their photodissociation spectroscopy and the dissociation dynamics of clusters. The first investigation is to be performed with a temperature variable selected ion flow tube which includes an electric drift field. The second is conducted with a high pressure ion source mass spectrometer and the third employs a molecular beam- intracavity laser apparatus with ion energy and mass analysis capabilities. Additionally, computational efforts involving ab initio quantum mechanics, classical trajectories, RRKM models, and phase-space theory are planned in order to augment the experimental phases of the program.

气溶胶的形成和化学作用是一个重要的 大气化学的一个方面， 明白 相当多的知识和洞察力， 气溶胶的形成，其随后的增长，以及化学物质 发生在内部或由其催化的转化 气溶胶可以通过研究气相 分子簇 关于集群的信息对于 确定核化前胚胎的稳定性， 阐述气体到粒子转化的理论。 集群 也提供了一个媒介，通过它详细了解 多相反应，包括金属离子的作用， 可以获得化学转化的光化学过程 在分子水平上。 这项研究项目涉及一项实验研究， 这三个主要领域将有助于阐明重要方面， 在上述过程中。 其中包括调查 （1）缔合（成簇）反应的动力学， 团簇与大气分子的后续反应; (2)团簇的热化学性质;（3） 团簇内的光化学反应，它们的光解离 光谱和集群的解离动力学。 的 第一次调查将在温度 包括电漂移的可变选择离子流管 领域 第二个是用高压离子源进行的 质谱仪，第三种采用分子束- 具有离子能量和质量分析内腔激光装置 能力的 此外，涉及ab的计算工作 量子力学，经典轨道，RRKM模型， 和相空间理论计划，以增加 该计划的实验阶段。