Carbonyl oxides as reactive intermediates in the lower atmosphere and the effect of optical excitation

低层大气中的碳酰氧化物作为反应中间体以及光激发的影响

• 批准号: 445396732
• 负责人: Professor Dr. Horst Köppel
• 金额: --
• 依托单位: Forschungsgruppe Theoretische Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/445396732?language=en
• 关键词: Carbonyl; oxides; reactive; intermediates; lower

For several years carbonyl oxides ("Criegees") are established as important reactive intermediates in the lower atmosphere whose role - especially upon electronic excitation - is nevertheless not well understood. In the project the spectroscopy and photophysics of electronically excited carbonyl oxides are to be investigated theoretically by a combination of accurate electronic structure computations and multidimensional wavepacket propagations on coupled potential energy surfaces. Thereby ambiguous experimental results and conflicting interpretations of the UV spectra of even the smallest system CH2OO are to be clarified. In addition to the spectral intensity profile also the internal conversion dynamics of the relevant (mostly singlet) excited states is of interest. From the results of these and related studies a coherent picture of the dynamics of these carbonyl oxides after photoexcitation is expected to emerge, which should provide the basis of a better understanding of the photochemical elementary processes in the lower atmosphere (troposphere). To arrive at conclusive results, the project focusses - as already indicated above - on carbonyl oxides with up to three carbon atoms; for a number of years the latter species are also subject to intense experimental investigations.

几年来，羰基氧化物（“Crieoxides”）被确定为低层大气中重要的反应中间体，但其作用--特别是在电子激发时--还没有得到很好的理解。在该项目中，电子激发的羰基氧化物的光谱和电子物理学将通过精确的电子结构计算和耦合势能面上的多维波包传播相结合进行理论研究。因此，即使是最小的系统CH 2 OO的紫外光谱的模糊的实验结果和相互矛盾的解释是要澄清。除了光谱强度分布，相关的（主要是单重态）激发态的内部转换动力学也是感兴趣的。从这些和相关研究的结果，这些羰基氧化物的动态光激发后的连贯画面，预计将出现，这应该提供的基础，更好地了解在低层大气（对流层）的光化学基本过程。如上文所述，为了取得结论性结果，该项目侧重于： 碳氧化合物最多有三个碳原子;数年来，后一种物质也受到密集的实验研究。