Heterogeneous Reactions of Chloride Salts in the Atmosphere: A Surface Science Approach

9707285本项目将利用表面科学技术，包括X射线光电子能谱和电子显微镜，探索固体氯化钠和水合盐(如氯化钙和氯化镁)与硝酸、五氧化二氮和硝酸氯等气体反应的基本动力学和机理。其他表面光谱技术，如高分辨率电子能量损失光谱和激光诱导解吸质谱，也将在项目期间得到必要的使用。将被研究的反应被认为分别有助于盐酸、硝基氯和分子氯的形成。后两者特别重要，因为它们的光解产生氯原子，在对流层中引发有机物的氧化时，氯原子可能与羟基竞争。将特别重视研究，以阐明水对这些反应的速率的重要性，以及在反应发生时表面结构的形态变化。

9707285 Hemminger This project will explore the fundamental kinetics and mechanisms of the reactions of solid sodium chloride and hydrated salts, such as calcium chloride and magnesium chloride, with gases such as nitric acid, dinitrogen pentoxide, and chlorine nitrate, using surface science techniques including x-ray photoelectron spectroscopy, and electron microscopy. Other surface spectroscopic techniques, such as high resolution electron energy loss spectroscopy and laser-induced desorption mass spectrometry, will also be used as warranted during the project. The reactions to be studied are believed to contribute to the formation of hydrochloric acid, nitryl chloride, and molecular chlorine, respectively. The latter two are of particular importance since their photolysis produces chlorine atoms which may compete with hydroxyl radicals in initiating the oxidation of organics in the troposphere. Particular emphasis will be placed on studies to elucidate the importance of water on the rates of these reactions and on morphological changes in the surface structure as the reactions occur.