Studies of negative ion spectroscopy and dynamics using time resolved photoelectron imaging

使用时间分辨光电子成像研究负离子光谱和动力学

• 批准号: 0350585
• 负责人: Daniel Neumark
• 金额: $ 58.7万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-02-01 至 2007-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0350585&HistoricalAwards=false
• 关键词: Studies; negative; ion; spectroscopy; dynamics

In this project, funded by the Experimental Physical Chemistry Program of the Chemistry Division, Daniel Neumark of the University of California at Berkeley will engage in spectroscopic and dynamical studies of negative ions and negative ion clusters by means of time-resolved photoelectron imaging (TRPEI) based on femtosecond pump-probe techniques. The approach is based on the successful work done under the previous grant, which is now extended into the domain of time resolution. Specifically, femtosecond-stimulated emission pumping will be used to coherently excite clustered negative I2 ions, and TRPEI will be used to track the resulting vibrational relaxation and solvent evaporation dynamics. Time-resolved pump-probe experiments on halide-water clusters will probe the dynamics of electron solvation in clusters. Time-resolved studies of bimolecular ion-molecule reactions, in particular gas-phase SN2 reactions, by photoinitiating a reaction with a femtosecond pump pulse and monitoring the subsequent dynamics by time-resolved photoelectron spectroscopy are also planned. The focus of the work is to understand the processes of photodetachment dynamics and cluster dynamics. This research will be conducted with postdoctoral research associates and graduate students, as well as undergraduates, who, through their participation in a forefront, cutting-edge research topic, will receive training in advanced research techniques in preparation for employment in the industrial, academic, or governmental sectors of the American economy.

在该项目中，由化学系实验物理化学项目资助，加州大学伯克利分校的Daniel Neumark将利用时间分辨光电子成像（TPEI）技术对负离子和负离子簇进行光谱和动力学研究。基于飞秒泵浦探测技术。 该方法基于先前资助下所做的成功工作，现在已扩展到时间分辨率领域。 具体来说，飞秒受激发射泵浦将用于相干激发簇状负 I2 离子，TRPEI 将用于跟踪由此产生的振动弛豫和溶剂蒸发动力学。 卤化物-水团簇的时间分辨泵浦探针实验将探测团簇中电子溶剂化的动力学。 还计划通过用飞秒泵浦脉冲光引发反应并通过时间分辨光电子能谱监测后续动力学，对双分子离子-分子反应（特别是气相 SN2 反应）进行时间分辨研究。 这项工作的重点是了解光脱离动力学和团簇动力学的过程。 这项研究将由博士后研究员、研究生以及本科生进行，他们通过参与前沿、前沿的研究课题，将接受先进研究技术的培训，为在工业、学术、或美国经济的政府部门。