水素转移异构的相对速率强烈依赖于多重结构的不和性
Lili Xing1, Junwei Lucas Bao2, Zhandong Wang3
1Energy and Power Engineering Institute , Henan University of Science and Technology , Luoyang , Henan 471003 , China.
Journal of the American Chemical Society
|November 24, 2018
概括
在燃料自燃中,基基 (OOQOOH) 是关键. 这项研究量化了它们的[1,5]转移,揭示了多结构不协调性对反应速率产生重大影响,这对燃烧和大气化学至关重要.
科学领域:
- 化学动力学
- 燃烧化学
- 理论化学
背景情况:
- 氧化类 (OOQOOH) 是运输燃料自燃中的关键中间体.
- 对OOQOOH基的关键[1,5]转反应的实验动力学数据很少.
- 了解OOQOOH反应动力学对于准确的燃烧建模至关重要.
研究的目的:
- 研究两个代表性的OOQOOH反应的动力学,重点是[1,5]转移.
- 阐明结构变化对不同[1,5]转移路径之间的竞争的影响.
- 为OOQOOH反应提供准确的速率常数,改进燃烧模型.
主要方法:
- 使用电子结构计算来确定热化学数据.
- 采用多维道和无调性校正 (包括扭曲和高频) 的变异过渡状态理论.
- 使用系统特定的量子赖斯-拉姆斯珀格-卡塞尔理论建模压力依赖.
主要成果:
- 在温度范围为2981500K的OOQOOH反应的计算速率常数.
- 确定了多结构不协调性,特别是由于扭曲,作为影响反应速率的主要因素.
- 观察到对相对速率的显著不和性,在室温下高达17倍,在1500K时高达7倍,即使对于类似的结构.
结论:
- 对于OOQOOH反应的精确速率常数,需要先进的理论方法来解释多结构不和性.
- 这些发现对燃烧和大气化学反应速率的估计有广泛的影响.
- 这项研究强调了复杂化学反应中基本的效应的重要性.
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