高压速率规则 乙烯基基基的基态异构化
Samah Y Mohamed1, Yeonjoon Kim2, Gina Fioroni1
1National Renewable Energy Laboratory, Golden, Colorado 80401, United States.
The journal of physical chemistry. A
|September 17, 2024
概括
这项研究详细介绍了乙烯基基基在以太中的同质化,这对于低温氧化至关重要. 计算的速率常数揭示了以太群影响,改善了精确的燃烧化学的动力模型.
科学领域:
- 化学动力学 化学动力学
- 燃烧化学 燃烧化学是什么
- 反应机制的反应机制
背景情况:
- 基基 (RO2) 基的异构化是低温氧化的关键,影响基基 (QOOH) 基的分支比率.
- 了解这些反应对于预测燃烧行为和控制污染物形成至关重要.
研究的目的:
- 系统地计算在单乙烯中RO2异构的高压速率规则.
- 为了研究环形大小,功能组位置和碳位点对反应速率的影响.
主要方法:
- 使用G4//B3LYP/6-311++G(2df,2pd) 层次理论和过渡状态理论.
- 计算了超过120个异构反应的速率常数和阿雷尼乌斯系数.
- 将以太异构化速率与类似的基反应进行比较.
主要成果:
- 确定了6和7个环的过渡状态,通常是最快的异构化途径.
- 由于以太函数组相对于过渡状态环的位置,观察到速率常数的显著差异.
- 与相似的基相比,发现了高达数量级的速率常数差异.
结论:
- 对于精确的低温燃烧建模,以太异构的特定场所速率常数是必不可少的.
- 乙烯基组的存在和位置显著改变了反应路径和速率.
- 应用的速率常数改进了二异乙烯动力模型,显著改变了分支比率.
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