2-甲基乙烯和2-甲基乙烯氧基的单分子反应
Anna C Doner1, Nicholas S Dewey1, Brandon Rotavera1,2
1University of Georgia, Department of Chemistry, Athens, Georgia 30602, United States.
The journal of physical chemistry. A
|August 3, 2023
概括
对2-甲基乙等循环乙烯的详细动力学研究对于准确的燃烧建模至关重要. 实验和计算揭示了复杂的反应途径,包括新型氧化,影响OH激素种群.
科学领域:
- 化学动力学 化学动力学
- 燃烧科学 燃烧科学
- 有机化学 有机化学
背景情况:
- 基替代循环乙烯是碳化合物和生物燃料氧化过程中的关键中间体.
- 它们随后的反应影响基 (H) 种群,对燃烧建模至关重要.
- 了解这些动力学对于高保真性燃烧模拟至关重要.
研究的目的:
- 为了研究2-甲基乙烯氧化过程的化学动力学.
- 阐明循环基及其产物的反应途径.
- 为改善燃烧化学动力模型提供数据.
主要方法:
- 在650K和800K时对2-甲基洛克塞坦进行Cl启动的氧化实验.
- 使用多重光电离子质谱法 (MPIMS) 进行物种检测.
- 使用KinBot算法和高层理论 (CCSD(T-F12/cc-pVDZ-F12) 来计算单分子反应的潜在能量表面.
主要成果:
- 从二甲基基 () 和氧基替代基 (Q̇OOH) 反应中确定了许多产物.
- 检测到的物种包括甲基,乙烯,甲,,,,1,3-丁,和acrolein.
- 从Q̇OOH环开放中观察到新的氧化 (酸,2-氧化) 和二基 (3-oxobutanal,2-methylpropanedial).
结论:
- 循环乙烯的氧化化学反应比目前燃烧模型中所代表的要复杂得多.
- Q̇OOH基的环开反应产生了具有潜在链分支效应的物种.
- 实验和计算数据强调了对循环乙烯燃烧的精细运动模型的需求.
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