Modeling Ozone Mass-Independent Fractionation (MIF) in Gas Phase and on Surfaces

模拟气相和表面上的臭氧质量无关分馏 (MIF)

• 批准号: 1252486
• 负责人: Dmitri Babikov
• 金额: $ 30.51万
• 依托单位: Marquette University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1252486&HistoricalAwards=false
• 关键词: Modeling; Ozone; Mass; Independent; Fractionation

This project will investigate the mass-independent fractionation (MIF) effect that leads to enrichment of stratospheric ozone in heavy isotopes of oxygen (17O and 18O). The theory for treating this ozone forming reaction will be further developed using a mixed quantum/classical method to characterize the collisional energy transfer without using reduced-dimension approximations. The use of several atmospheric bath gases will be studied as quenchers for the reaction. The MIF of oxygen in the ozone-forming reaction has been shown to disappear when a very efficient molecular quencher, such as SF6, is used. The emphasis of the project will be on moving from the analytic model to a master-equation treatment of the kinetics. The project will also include the first-ever quantum dynamic calculations for the formation of ozone on surfaces.The mass-independent fractionation (MIF) of O3 has a significant impact on our understanding of the ozone's chemistry, production, lifetime and loss in the atmosphere, and the effect ozone has on global climate change. The advances made in further elucidating the MIF of O3 will provide the key to understanding the MIF for several other molecules, such as stratospheric CO2, N2O and CO. The isotopic composition of atmospheric CO2 is often used to identify its sources and further characterization of the MIF of CO2 will lead to an increased understanding of the global carbon budget.

该项目将调查导致平流层臭氧富集氧的重同位素（17 O和18 O）的质量无关分馏效应。处理这种臭氧形成反应的理论将进一步发展使用混合量子/经典方法来表征碰撞能量转移，而不使用降维近似。将研究使用几种大气压浴气作为反应的淬灭剂。当使用非常有效的分子猝灭剂（如SF6）时，臭氧形成反应中氧的MIF已被证明消失。该项目的重点将是从分析模型移动到动力学的主方程处理。该项目还将包括首次对臭氧在表面形成的量子动力学计算。O3的质量无关分馏（MIF）对我们理解臭氧的化学、产生、寿命和在大气中的损失以及臭氧对全球气候变化的影响有着重大影响。在进一步阐明的MIF的O3的进展将提供关键的理解MIF的其他几个分子，如平流层CO2，N2 O和CO。大气CO2的同位素组成通常用于确定其来源和进一步表征的MIF的CO2将导致增加对全球碳预算的理解。