克里吉中间体CH2OO与阿利法性化物反应的温度依赖动力学
Jonas J Enders1, Zachary A Cornwell1, Aaron W Harrison2
1Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States.
The journal of physical chemistry. A
|September 5, 2024
概括
克里吉中间体与甲基化物 (如甲) 反应. 它们的反应速度随着温度的增加而下降,这表明大气作用很小.
科学领域:
- 大气化学 大气化学
- 化学动力学 化学动力学
- 计算化学的计算化学
背景情况:
- 克里基中间体是热层臭氧化学中的关键物种.
- 它们与挥发性有机化合物的反应影响空气质量.
研究的目的:
- 为了研究Criegee中间体 (CH2OO) 反应的动力学与小的阿利法性化物.
- 确定这些反应的温度依赖性.
主要方法:
- 使用了激光闪光光解短暂吸收光谱学.
- 使用ab initio计算来支持实验发现.
主要成果:
- 确定了与甲,乙甲和甲反应的双分子速率常数.
- 所有反应都表现出在275-335K之间的负温度依赖.
- 反应机制涉及1,3-双极循环添加,形成三索兰中间体.
结论:
- 速率常数随着温度的增加而下降,遵循阿雷尼乌斯的行为.
- 尽管它们形成,但由于Criegee中间体度低,这些反应在大气化学中不太可能具有意义.
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