RUI: Spectroscopic Studies of Cyclic Conjugated Molecules in Triplet (n,pi*) Excited States

RUI：三重态 (n,pi*) 激发态环状共轭分子的光谱研究

• 批准号: 0848615
• 负责人: Stephen Drucker
• 金额: $ 22.23万
• 依托单位: University of Wisconsin-Eau Claire
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-15 至 2014-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0848615&HistoricalAwards=false
• 关键词: RUI; Spectroscopic; Studies; Cyclic; Conjugated

In this project, funded by the Experimental Physical Chemistry Program of the Chemistry Division, Prof. Stephen Drucker and his undergraduate students at the University of Wisconsin-Eau Claire will continue their spectroscopic studies of small organic molecules in triplet excited states. Triplet states (species having two unpaired electrons) play a central role in many photochemical reactions. Prof. Drucker and his group have been investigating the lowest triplet states of a series of cyclic conjugated enone molecules. They have explored structural and dynamical differences between the triplet states and their singlet counterparts. Beyond the fundamental insights offered by such investigation, the experiments provide benchmark spectroscopic information for testing or refining computational treatments of excited states and the photochemical processes they mediate. In the proposed research, students will use sensitive spectroscopic techniques - cavity ringdown absorption and phosphorescence excitation - to determine frequencies of the C=O and C=C stretching vibrations in the triplet states. The data will complement information that the group obtained previously on low-frequency ring vibrations of the cyclic enones. The researchers will also extend their work to include lactone and anhydride molecules analogous to the enones. Heretofore, the information available from the room temperature spectra has been limited by spectral congestion due to hot bands. To eliminate the hot bands, Prof. Drucker's group proposes to record the cavity ringdown spectra under jet-cooled conditions using a slit nozzle source. In this project, undergraduate group members will conduct in-depth research. Such opportunities add substantial value to the undergraduate education program, and can also foster rich opportunities for advanced study. Ongoing collaborations (with investigators at Purdue, Texas A&M, and USC) will enable Prof. Drucker's undergraduates to participate in a range of activities. In turn, graduate students in the collaborating research groups will be able to explore faculty careers at undergraduate institutions as they interact with Prof. Drucker and his students from UW-Eau Claire.

在这个由化学系实验物理化学计划资助的项目中，威斯康星大学欧克莱尔分校的Stephen Drucker教授和他的本科生将继续他们对三重激发态小有机分子的光谱研究。三重态（具有两个未成对电子的物质）在许多光化学反应中起着核心作用。Drucker教授和他的团队一直在研究一系列环状共轭烯酮分子的最低三重态。他们探索了三重态和单重态之间的结构和动力学差异。除了这种调查提供的基本见解，实验提供了基准光谱信息的测试或改进计算处理的激发态和它们介导的光化学过程。在拟议的研究中，学生将使用灵敏的光谱技术-腔衰荡吸收和磷光激发-来确定三重态中C=O和C=C伸缩振动的频率。这些数据将补充该小组先前获得的关于环状烯酮低频环振动的信息。研究人员还将扩展他们的工作，包括类似于烯酮的内酯和酸酐分子。因此，从室温光谱中获得的信息受到由于热带引起的光谱拥塞的限制。为了消除热带，Drucker教授的小组建议使用狭缝喷嘴源在喷射冷却条件下记录腔衰荡光谱。在本项目中，本科生小组成员将进行深入研究。这样的机会增加了本科教育计划的实质性价值，也可以培养丰富的深造机会。正在进行的合作（与普渡大学，得克萨斯州A M和南加州大学的研究人员）将使德鲁克教授的本科生参加一系列活动。反过来，合作研究小组的研究生将能够探索本科院校的教师职业，因为他们与德鲁克教授和他的学生从UW-Eau Claire互动。