Reactions in Organized and Constricted Systems

有组织和受限系统中的反应

• 批准号: 9204420
• 负责人: J. Kerry Thomas
• 金额: $ 39.45万
• 依托单位: University of Notre Dame
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-06-15 至 1996-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9204420&HistoricalAwards=false
• 关键词: Reactions; Organized; Constricted; Systems

The ability of molecular cations to migrate and undergo chemical reactions will be determined in a variety of different environments including low viscosity liquids at room temperature, glasses at 77 K, and highly viscous oligomers and polymers. Polymers to be investigated range from chloropolymers such as polyvinylchloride to polystyrene and polyethylene. The cationic species will be generated by exposure of polycyclic hydrocarbons such as anthracene, naphthalene, and pyrene to high-energy radiation produced from a Fabretron. The resulting cationic species will be detected by transient spectroscopy on a picosecond time scale. In addition to the kinetic analysis of the cation migration rate, an investigation of the rate of fluorescence quenching of both absorbed and surface bound pyrene at solid-air and solid-liquid interfaces of silicon oxide will be conducted. The effect of the surface on the generation of charged species from exciplexes will also be determined by diffuse reflectance transient absorption spectroscopy. The results of these investigations will lead to a better understanding of the reactions of cationic species at surfaces and the factors governing efficient quenching processes. %%% This grant from the Organic Dynamics Program supports the continuing work of Professor J. Kerry Thomas at the University of Notre Dame. The studies will be directed toward understanding the effect of surfaces on the reactivity of chemical substances and will provide critical data which will allow the development of more efficient chemical systems. The investigation will utilize equipment capable of detecting events on the order of less than a billionth of a second. Thus it will be possible to measure the rapid hopping of charged species in a variety of media. The use of target molecules which undergo rapid fluorescence decay processes provides a means of monitoring chemical processes on a time scale which would otherwise be inaccessible.

分子阳离子迁移和经历的能力 化学反应将在各种不同的 包括室内低粘度液体的环境 温度，77 K下的玻璃，和高粘度低聚物， 聚合物要研究的聚合物范围从 氯聚合物如聚氯乙烯到聚苯乙烯， 聚乙烯。阳离子物质将通过以下方式产生： 接触多环烃如蒽， 萘和芘产生的高能辐射 一个法布创。所得阳离子物质将通过 皮秒时间尺度上的瞬态光谱学。此外 阳离子迁移速率的动力学分析， 研究了两者的荧光猝灭速率， 固-气、固-液吸附态和表面结合态芘 氧化硅的界面将被传导。的影响 表面上产生的带电物质， 激基复合物也将由漫反射率确定 瞬态吸收光谱的结果予以 调查将有助于更好地了解 阳离子物种在表面的反应及其影响因素 控制有效的淬火过程。 %%% 有机动力学计划的这笔赠款支持 J. Kerry托马斯教授在该大学的持续工作 巴黎圣母院这些研究将针对 了解表面对反应性的影响， 化学物质，并将提供关键数据， 从而开发出更高效的化学系统。的 调查将使用能够检测 发生在十亿分之一秒以内的事件。因此 将有可能测量带电粒子的快速跳跃， 各种媒体中的物种。靶分子的用途 其经历快速的荧光衰减过程， 在时间尺度上监测化学过程的手段， 否则将无法访问。