Dissociative Photodetachment Dynamics of Multiply Charged Anions

多电荷阴离子的解离光脱离动力学

• 批准号: 1464548
• 负责人: Robert Continetti
• 金额: $ 51.58万
• 依托单位: University of California-San Diego
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1464548&HistoricalAwards=false
• 关键词: Dissociative; Photodetachment; Dynamics; Multiply; Charged

With this award, the Chemical Structure, Dynamics, and Mechanism (CSDM-A) Program in the Division of Chemistry supports Dr. Robert Continetti at the University of California-San Diego in his studies of isolated multiply charged anions. These molecules with extra electrons play an important role in a wide range of chemistry, including biological systems, catalysts and as building blocks in ionic solids. However, they are very difficult to study experimentally in an isolated state. This research program involves novel measurements of the stability and chemistry of isolated multiply charged anions, with the information gained providing new insights and guiding the development of an improved theoretical understanding of these important chemical building blocks. Students involved in this project are learning about the design, construction and chemical application of a unique apparatus. The PI also uses contacts with local industry in San Diego (Cymer, Illumina, Air Products and others) to arrange quarterly tours of industrial labs and seminars by industrial scientists to enhance the career development of underrepresented minority and women graduate students across the Dept. of Chemistry and Biochemistry at UCSD.On a more technical level, this award enables experimental studies of the energetics, photochemistry and dissociation dynamics of multiply charged anions (MCAs) with a particular focus on dissociative photodetachment. Isolated MCAs are challenging systems for study theoretically and experimentally, but important progress has been made using photoelectron and photodissociation spectroscopies. However, many MCAs can undergo complex multiple photodetachment and dissociation processes. These studies use an electrospray ionization source coupled with a cryogenic accumulator ion trap prior to injection into a high-energy electrostatic ion beam trap where the photoelectron and photofragment measurements are made. Time- and position-sensitive detectors are used to make three-dimensional, kinematically complete measurements of the photodetachment, multiple photodetachment, photodissociation and dissociative photodetachment processes observed. In addition, the lifetimes of metastable polyanions and photofragment anions are measured in the electrostatic ion beam trap. The first focus of the project is on the stable dianions formed from dicarboxylic acids, later to be extended to phthalocyanines and biologically relevant sulfonates. In a collaboration with the synthetic inorganic laboratory of Figueroa at UCSD, novel metal carbonyl and isocyanide complexes synthesized for applications in catalysis are also under study. For these systems, there is no prior experimental information available on the ligand dissociation processes and electron-capture energetics that this project is providing. This information is essential for guiding the design of future catalysts and the development of an improved theory of MCAs.

有了这个奖项，化学部的化学结构，动力学和机制（CSDM-A）计划支持加州大学圣地亚哥分校的Robert Continetti博士研究孤立的多电荷阴离子。这些具有额外电子的分子在广泛的化学中发挥着重要作用，包括生物系统，催化剂和离子固体中的构建块。然而，它们很难在孤立状态下进行实验研究。该研究计划涉及对孤立的多电荷阴离子的稳定性和化学性质的新测量，所获得的信息提供了新的见解，并指导了对这些重要化学构件的理论理解的发展。参与该项目的学生正在学习一种独特装置的设计、构造和化学应用。 PI还利用与圣地亚哥当地行业（Cymer，Illumina，Air Products等）的联系，安排工业科学家每季度图尔斯工业实验室和研讨会，以提高整个部门代表性不足的少数民族和女性研究生的职业发展。在更技术的层面上，该奖项使多电荷阴离子（MCAs）的能量学，光化学和解离动力学的实验研究成为可能，特别关注解离光分离。孤立的MCA在理论和实验上都是具有挑战性的研究体系，但利用光电子和光解离光谱学已经取得了重要进展。然而，许多MCA可以经历复杂的多重光分离和解离过程。这些研究使用的电喷雾电离源耦合到一个低温蓄电池离子阱注入到一个高能量的静电离子束阱的光电子和photorefraction测量之前。时间和位置敏感的探测器被用来进行三维，运动学完整的测量的光剥离，多个光剥离，光解离和解离光剥离过程中观察到的。此外，在静电离子束阱中测量了亚稳态聚阴离子和光致碎片阴离子的寿命。该项目的第一个重点是由二羧酸形成的稳定的二价阴离子，后来扩展到酞菁和生物相关的磺酸盐。在与加州大学圣地亚哥分校的Figueroa合成无机实验室的合作中，还在研究用于催化的新型金属羰基和异氰化物复合物。对于这些系统，有没有以前的实验信息提供的配体解离过程和电子捕获能量，这个项目提供。这些信息对于指导未来催化剂的设计和改进的MCAs理论的发展至关重要。