Dynamics of Ion-Radical Collisions: Imaging Studies

离子自由基碰撞动力学：成像研究

• 批准号: 1012303
• 负责人: James Farrar
• 金额: $ 45.55万
• 依托单位: University of Rochester
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-15 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1012303&HistoricalAwards=false
• 关键词: Dynamics; Ion; Radical; Collisions; Imaging

In this project supported by the Chemical Structure, Dynamics and Mechanisms Program and the Chemical Measurement and Imaging Program of the Division of Chemistry, Professor James Farrar of the University of Rochester and his research group will explore the collisions of free radicals and atomic or molecular ions. By employing a pulsed supersonic source of free radicals such as CH3 and C3H5, and an electron impact or discharge source of low energy cations such as N2+, N+, C+, Si+, and S+, and anions such as O-, O2-, and OH-, velocity space imaging methods will be used to detect the products of the reactions, yielding differential cross sections in kinetic energy and angle. Of particular interest are the bond formation reactions that yield C-C, C-O, C-N, N-O, S-C, and Si-C bonds. For anionic reactions, free electrons produced by associative detachment will also be detected. The experiments will represent the first dynamical studies of the reactions of low energy ions with free radicals and will address the serious deficiencies of models for electrical discharges and the chemistry of planetary atmospheres that do not include ion-radical reactions.In addition to characterizing the dynamics of the aforementioned chemical systems, this research will provide a deeper understanding of reactivity patterns and a molecular understanding of the chemistry that takes place in electrical discharges such as those involved in reactive ion etching, and in atmospheric and extraterrestrial chemistry. The instrumental technique development may have impacts in various subdisciplines of chemistry, including mass spectrometry and ion imaging. The graduate and undergraduate students and post-doctoral associates involved in this research will contribute to the national scientific and economic infrastructure through the development of new measurement technologies, new high value-added products, and the further training of scientific personnel.

在这个由化学系化学结构、动力学和机理计划以及化学测量和成像计划支持的项目中，罗切斯特大学的詹姆斯·法勒教授和他的研究小组将探索自由基与原子或分子离子的碰撞。通过使用CH3和C3H5等脉冲超音速自由基源，以及低能阳离子如N+、N+、C+、Si+和S+以及阴离子如O-、O2-和OH-的电子撞击或放电源，将使用速度空间成像方法来检测反应产物，获得动能和角度的不同截面。特别令人感兴趣的是生成C-C、C-O、C-N、N-O、S-C和Si-C键的成键反应。对于阴离子反应，还将检测到缔合脱离产生的自由电子。这些实验将是对低能离子与自由基反应的第一次动力学研究，并将解决电放电模型和不包括离子自由基反应的行星大气化学的严重缺陷。除了描述上述化学系统的动力学之外，这项研究还将提供对反应模式的更深层次的理解，以及对发生在电放电中的化学的分子理解，例如涉及反应离子刻蚀的化学以及大气和地外化学中的化学。仪器技术的发展可能会对化学的各个分支学科产生影响，包括质谱学和离子成像。参与这项研究的研究生、本科生和博士后研究员将通过开发新的测量技术、新的高附加值产品和进一步培养科学人才，为国家科学和经济基础设施做出贡献。