化碳酸盐中电子触发过程:CF3COCl及其集群中的解离途径
Barbora Kocábková1, Jozef Ďurana1, Jozef Rakovský1
1J. Heyrovský Institute of Physical Chemistry, v.v.i., Czech Academy of Sciences, Dolejškova 2155/3, 18223 Prague 8, Czech Republic. michal.farnik@jh-inst.cas.cz.
Physical chemistry chemical physics : PCCP
|January 30, 2024
概括
研究了三乙化 (CF3COCl) 与电子的反应性. 电子附着导致C-Cl或C-C键断裂,形成负离子. 集群研究显示稳定和新的离子形成.
科学领域:
- 大气化学 大气化学
- 物理化学 物理化学
- 化学物理 化学物理
背景情况:
- 三乙化 (CF3COCl) 是碳化合物的大气降解产物.
- 它是反应性基的潜在来源.
- 它的电子反应性以前没有被研究过.
研究的目的:
- 为了研究孤立的CF3COCl分子及其集群的电子电离和附着.
- 了解碎片化路径和离子形成.
- 为了探索潜在的大气影响.
主要方法:
- 分子束实验. 分子束实验.
- 电子电离和附着研究.
- 量子化学计算 量子化学计算
主要成果:
- 在70 eV的电子电离会导致C-C和C-Cl键的碎片化,产生CF3+,COCl+和CF3CO+离子.
- 在3 eV以下的电子附着主要会破坏C-Cl键,形成Cl-离子.
- 4 eV以上的电子附着会破坏C-C键,形成CF3-离子.
- 集群研究表明完整的负离子的稳定和M·Cl2-离子的形成.
结论:
- 在电子冲击时,CF3COCl经历了显著的碎片化,无论是在孤立的分子中还是集群中.
- 电子附着导致特征性的键解离和负离子形成.
- 这些发现提供了关于大气过程中CF3COCl的电子诱导化学的见解.
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