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关于酸与最简单的芳香Criegee中间体的机制和动力学的理论研究

Guangliang Chen¹, Mingqiang Huang¹, Guangzhen Gao²

¹Fujian Provincial Key Laboratory of Modern Analytical Science and Separation Technology, College of Chemistry & Chemical Engineering and Environment, Minnan Normal University Zhangzhou 363000 China huangmingqiang@mnnu.edu.cn.

|September 5, 2025

概括

酸 (HONO) 与芳香Criegee中间体的反应形成含的有机化合物 (NOC). 原子转移是主要的途径,产生甲化.

科学领域:

大气化学
化学动力学
计算化学

背景情况:

酸 (HONO) 是一个重要的大气污染物.
芳香的Criegee中间体,如PhCHOO,是大气氧化过程中的关键物种.
从HONO反应中获得的含有机化合物 (NOC) 有助于气溶的形成.

研究的目的:

研究HONO和最简单的芳香Criegee中间体 (PhCHOO) 之间的反应机制和动力学.
阐明主要的反应途径及其对NOC形成的贡献.
提供有关大气气溶生成的理论见解.

主要方法:

用密度函数理论 (DFT) 的计算来探索潜在的能量表面.
使用过渡状态理论 (TST) 来确定反应速率常数.
使用计算建模分析反应路径和激活能量.

主要成果:

形成异构的循环添加途径具有高激活能量和低速率常数,表明它不是主导反应.
氧原子转移和循环添加途径可以产生酸 (HNO3) 和酸.
原子转移是主要的途径,产生具有最低激活能量和显著速率常数 (5.68 × 10−13 cm3 分子−1 s−1) 的氧化甲.

结论:

HONO和PhCHOO之间的反应主要由原子转移路径控制.
这项研究确定了Ph-HPMN是HONO与芳香Criegee中间体反应的关键产物.
这些发现为了解在HONO存在下,烯和类似化合物的臭氧化形成提供了理论基础.

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