On the Theoretical Determination of Photolysis Properties for Atmospheric Volatile Organic Compounds
On the Theoretical Determination of Photolysis Properties for Atmospheric Volatile Organic Compounds
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DOI：
10.1021/acs.jpclett.0c01439
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发表时间：
2020-07-16
影响因子：
5.7
通讯作者：
Curchod, Basile F. E.
中科院分区：
文献类型：
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作者：
Prlj, Antonio;Ibele, Lea M.;Curchod, Basile F. E.
挥发性有机化合物(VOC)是普遍存在的大气分子，在对流层中产生复杂的化学反应网络，通常由阳光的吸收引发。了解大气中挥发性有机化合物的组成依赖于我们描述它们所有可能的反应路径的能力。当考虑(瞬时)VOCs与阳光的反应时，由于这些分子的不稳定性质，在一般大气模型中使用的光解速率常数的可用性通常不在实验范围之内。在这里，我们展示了计算光化学的最新进展如何使我们能够计算光解速率常数的不同成分，即光吸收截面和与波长相关的量子产率。利用叔丁基氢过氧化氢丰富的光化学实验数据对我们的方案进行了验证，突出了不同水平的电子结构和非绝热分子动力学在研究(瞬时)VOCs的光化学方面的优缺点。
Volatile organic compounds (VOCs) are ubiquitous atmospheric molecules that generate a complex network of chemical reactions in the troposphere, often triggered by the absorption of sunlight. Understanding the VOC composition of the atmosphere relies on our ability to characterize all of their possible reaction pathways. When considering reactions of (transient) VOCs with sunlight, the availability of photolysis rate constants, utilized in general atmospheric models, is often out of experimental reach due to the unstable nature of these molecules. Here, we show how recent advances in computational photochemistry allow us to calculate in silico the different ingredients of a photolysis rate constant, namely, the photoabsorption cross-section and wavelength-dependent quantum yields. The rich photochemistry of tert-butyl hydroperoxide, for which experimental data are available, is employed to test our protocol and highlight the strengths and weaknesses of different levels of electronic structure and nonadiabatic molecular dynamics to study the photochemistry of (transient) VOCs.