Experimental and theoretical studies of novel HOx-NOx reactions in the atmosphere

这是一项关于研究对大气化学有重大影响的关键反应的提议。通过结合实验和理论，将充分表征一些反应，这些反应耦合低层和中层大气的HOx和NOx自由基家族，并深刻地改变光化学臭氧的产生： → HNO3 + M （R1b）NO2* + H2O → OH + HONO （R2b）NO3* + H2O → OH + HNO3 （R3b）OH + HNO3 → NO3 + H2O （R4）这些反应的动力学/机理数据库状况不佳。先进的实验技术和理论方法将被采用，特别是验证最近的建议HNO 3形成的HO 2和NO之间的反应（R1 b），和OH自由基的形成通过非解离光激发的NO2和NO3在水蒸气的存在下（R2 b，R3 b）。R4的速率系数在低温下是高度不确定的。这些反应的机制的基本理解是获得和可靠的动力学数据，为大气建模将提供。

This is a proposal for research into key reactions that substantially impact on atmospheric chemistry. By combining experiment and theory a number of reactions which couple the HOx and NOx radical families of the lower and middle atmosphere and profoundly modify photochemical ozone production will be fully characterised:HO2 + NO + M → HNO3 + M (R1b)NO2* + H2O → OH + HONO (R2b)NO3* + H2O → OH + HNO3 (R3b)OH + HNO3 → NO3 + H2O (R4)The kinetic/mechanistic database for these reactions is in poor shape. Advanced experimental techniques and theoretical methods will be employed in particular to verify the recent suggestion of HNO3 formation in the reaction between HO2 and NO (R1b), and the formation of OH radicals via non-dissociative photo-excitation of NO2 and NO3 in the presence of water-vapour (R2b, R3b). The rate coefficient for R4 is highly uncertain at low temperatures. A fundamental understanding of the mechanisms of these reactions is to be obtained and reliable kinetic data for atmospheric modeling will be provided.