Partitioning of Light Energy Absorbed by Organic Chemicals

这项研究主要集中在两个主题上：分子结构对局域光子激发能量的影响，以及由此产生的反应活性的选择性。将测量一系列结构相关的酮分子内抽氢量子效率的温度依赖性，以区分由能量变化控制的过程和由表面交叉几率变化控制的过程。分子内抽氢产生的双自由基光诱导环化率相对于其他竞争过程的温度依赖关系将与双自由基结构的理论计算相关联，以阐明结构对系间交叉的作用。研究生和博士后将接受有机合成和机械有机光化学方面的培训。通过这一奖项，有机和高分子化学项目支持密歇根州立大学化学系的Peter Wagner博士的研究。光的吸收使分子的能量突然增加，从而增强了它的反应性。瓦格纳博士将把他的研究重点放在阐明被激发的分子将实现特定反应所需的能量定位的过程，并确定影响能量定位的结构参数。瓦格纳博士的教育活动包括培训研究生和博士后学习有机合成，以及测量和表征激发态过程。

This research focuses on two general themes; the effect of molecular structure on localizing photonic excitation energy, and the selectivity of the resulting reactivity. The temperature dependence of the quantum efficiency of intramolecular hydrogen abstraction will be measured for a series of structurally related ketones to distinguish processes controlled by changes in energy from those controlled by variations in surface crossing probabilities. The temperature dependence of the ratio of photoinduced cyclization in biradical arising from intramolecular hydrogen abstraction, relative to other competing processes, will be correlated with theoretical computations of biradical structure to elucidate the role of structure on intersystem crossing. Graduate and postdoctoral students will be trained in organic synthesis and mechanistic organic photochemistry. With this award, the Organic and Macromolecular Chemistry Program supports the research of Dr. Peter Wagner of the Department of Chemistry at Michigan State University. The absorption of light causes an abrupt increase in a molecule's energy thereby enhancing its reactivity. Dr. Wagner will focus his research on elucidating the processes by which the excited molecule localizes the energy needed to achieve a specific reaction, and identifying the structural parameters that affect this energy localization. Dr. Wagner's educational activities involve training graduate and postdoctoral students in organic synthesis, and the measurement and characterization of excited-state processes.