High-Accuracy Thermochemistry with Threshold and Imaging Photoelectron Photoion Coincidence Spectroscopy

具有阈值和成像光电子光电离子符合光谱的高精度热化学

• 批准号: 1266407
• 负责人: Balint Sztaray
• 金额: $ 40.3万
• 依托单位: University of the Pacific
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-15 至 2017-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1266407&HistoricalAwards=false
• 关键词: Accuracy; Thermochemistry; Threshold; Imaging; Photoelectron

Through this award, funded by the Chemical Structure, Dynamics, and Mechanisms - A Program of the Division of Chemistry, Prof. Bálint Sztáray from the University of the Pacific, will characterize the thermochemistry of molecules and radicals that have combustion or atmospheric relevance. Using Photoelectron Photoion Coincidence Spectroscopy, significant improvements will be offered to three of the most important parameter sets in combustion and atmospheric models: accurate experimental thermochemical data, reaction rates, and energy distributions. The experiments will be conducted both on the lab-based instrument at the University of the Pacific, which will receive an upgrade of a new ion velocity map imaging setup, and on the Imaging Photoelectron Photoion Coincidence Spectroscopy endstation at the Swiss Light Source synchrotron. Combining experimental ion fragmentation and velocity distribution data with high-level quantum chemical calculations, advances will be offered in the understanding of statistical rate and energy distribution theories to improve the kinetics modeling tools used in combustion and atmospheric models.Energy is arguably the most important physical quantity, affecting almost every aspect of physical, chemical and biological processes. Chemical changes in the structure of molecules are almost invariably accompanied by changes in the energy, determining which chemical reactions are possible. As the primary purpose of combustion processes is to extract energy from chemical systems, characterizing the energy content of the various molecules and fragments involved in combustion is the foundation on which predictive models can be built. Thermochemistry, the study of the role of energy in chemical processes, has gone through transformative changes in the last decade, partly due to advances in computational methods and party due to new holistic models in which energy changes in remotely related systems are connected in a complex web of energy relationships. Computational methods in the past few years have approached and even exceeded experimental accuracy and they need new and more accurate experimental data to be tested against. The experimental methods used in this research will provide some of the most accurate numbers on a wide variety of systems that are involved in combustion or atmospheric processes.

太平洋大学的Bálint Sztáray教授将通过这一由化学结构、动力学和机制-化学系项目资助的奖项，表征与燃烧或大气相关的分子和自由基的热化学。利用光电子光离子符合谱，燃烧和大气模型中最重要的三个参数集将得到显著改进：准确的实验热化学数据、反应速率和能量分布。这些实验将在太平洋大学的实验室仪器和瑞士光源同步加速器的成像光电子光离子符合光谱分析终端站上进行，太平洋大学的实验室仪器将接受新的离子速度图成像装置的升级。将实验离子碎裂和速度分布数据与高级量子化学计算相结合，将在理解统计速率和能量分布理论方面取得进展，以改进用于燃烧和大气模型的动力学建模工具。能量可以说是最重要的物理量，几乎影响到物理、化学和生物过程的方方面面。分子结构的化学变化几乎总是伴随着能量的变化，这决定了哪些化学反应是可能的。由于燃烧过程的主要目的是从化学体系中提取能量，因此表征燃烧过程中涉及的各种分子和碎片的能量含量是建立预测模型的基础。热化学研究能量在化学过程中的作用，在过去十年中经历了变革性的变化，部分原因是计算方法的进步和新的整体模型，其中远程相关系统中的能量变化以复杂的能量关系网络连接在一起。过去几年的计算方法已经接近甚至超过了实验精度，它们需要新的、更准确的实验数据来进行测试。这项研究中使用的实验方法将提供涉及燃烧或大气过程的各种系统的一些最准确的数字。