NSF New Young Investigator Award - Transition State Chemistry in Photodissociation and Chemical Reactions

加州大学伯克利分校的陈永勤教授将在美国国家科学基金物理化学计划的这一项目中，实时研究光解离和化学反应中的过渡态化学。这将通过他设计的一种新技术--瞬变受激发射泵浦(TSEP)来实现，该技术能够在飞秒时间尺度上探测化学过程。这些研究将在气体系统和超临界流体上进行。化学反应动力学处于当前化学研究的前沿。化学反应如何进行的细节只能在一个分子振动周期或更小的时间尺度上进行研究。要进行这样的调查，需要具有超快时间分辨率的实验技术，时间尺度从皮秒到飞秒。与目前使用的其他技术相比，新的TSEP技术具有相当大的优势，例如，通过同时生成整个受激发射光谱，而不是通过逐点扫描。

In this National Science Foundation New Young Investigator (NYI) project of the Physical Chemistry Program in the Chemistry Division Prof. Yongqin Chen of the University of California at Berkeley will investigate the transition state chemistry in photodissociation and chemical reactions in real-time. This will be accomplished with a new technique of his design, transient stimulated emission pumping (TSEP), which enables the probing of chemical processes on a femtosecond time scale. These investigations will be performed on gaseous systems as well as on supercritical fluids. %%% Chemical reaction dynamics is at the forefront of present research in chemistry. The details of how a chemical reaction proceeds can only be studied on time scales which are of the order of the period of one molecular vibration or less. To carry out such investigations requires experimental techniques with ultra fast time resolution, on time scales ranging from pico- to femtoseconds. The new TSEP technique possesses considerable advantages over other, currently used techniques by, for example, generating an entire stimulated emission spectrum simultaneously rather than by point-by-point scanning.