Spectroscopic Detection and Characterization of Chemical Intermediates

在化学学部物理化学项目中，俄亥俄州立大学的Terry A. Miller教授将对化学反应中间体及其相关簇进行基础研究。检测和表征该物种的主要方法是高分辨率光谱。这些物质是在低温、无反应的超音速射流膨胀环境中产生的，在那里它们可以通过中等和非常高分辨率的激光诱导荧光（LIF）光谱进行检测。使用相同的射流技术，零动能（ZEKE）光谱的化学上非常重要的离子的一些反应性，中性自由基将表征。作为中性和/或阳离子研究的特定化学中间体包括烷氧自由基及其氟和硫衍生物、碳烯、氨基根和相关自由基以及取代甲基自由基（碳酸离子）。同时在基础光谱学理论，应用光谱学分析和从头计算化学中间体的理论发展将进行。在大气、燃烧和有机合成过程中发生的复杂化学反应通常涉及瞬态化学中间体，如自由基和分子离子，它们决定了整个过程的结果。中间体的光谱鉴定对于此类反应的实际研究和监测至关重要。中间体的光谱表征为化学反应性质的基本认识提供了基础。本研究涉及到这些中间体和涉及它们的物种的光谱检测和表征的多方面方法。

In this project in the Physical Chemistry Program of the Chemistry Division, Prof. Terry A. Miller of the Ohio State University will conduct fundamental investigations of chemical reaction intermediates and clusters involving them. The primary method for detection and characterization of the species is high resolution spectroscopy. The species are produced in the cold, unreactive environment of a supersonic jet expansion where they can be interrogated by bot moderate and very high resolution laser induced fluorescence (LIF) spectroscopy. Using the same jet techniques, the zero kinetic energy (ZEKE) spectroscopy of the chemically very important ions of a number of reactive, neutral free radicals will be characterized. Specific chemical intermediates to be studied as neutrals and/or cations include alkoxy radicals and their fluoro- and thio-derivatives, carbenes, amiodogen and related radicals, and substituted methyl radicals (carbonium ions). Concurrent theoretical developments in fundamental spectroscopic theory, applied spectroscopic analysis, and ab initio calculations on the chemical intermediates will be undertaken. Complex chemical reactions that occur in atmospheric, combustion, and organic synthesis processes typically involve transient chemical intermediates, such as free radicals and molecular ions, that determine the overall result of the process. Spectroscopic identification of the intermediates is critical for the practical investigation and monitoring of such reactions. Spectroscopic characterization of the intermediates provides a foundation for the basic understanding of the nature of chemical reactivity. This research involves a multifaceted approach to the spectroscopic detection and characterization of these intermediates and species involving them.