变量过渡状态理论作为一种工具,用于确定涉及山谷 - 丘陵拐点反应中的动力选择性
Angels Ganzález-Lafont1, Miquel Moreno, José M Lluch
1Contribution from the Departament de Química, Universitat Autonoma de Barcelona, 08193 Bellaterra (Barcelona), Spain.
Journal of the American Chemical Society
|October 8, 2004
概括
这项研究计算了单片氧与四甲基乙烯反应的动态同位素效应. 变化过渡状态理论揭示了H和D抽象的明显瓶,KIE为1.126在263K.
科学领域:
- 化学动力学 化学动力学
- 理论化学是一种理论化学.
背景情况:
- 单片氧 ((1) O ((2)) 反应在大气化学和生物学中至关重要.
- 了解反应机制和产品分布对于预测化学行为至关重要.
研究的目的:
- 计算单片氧与d(6) -四甲基乙烯反应的动态同位素效应 (KIEs).
- 在这个反应中研究控制产品比率的动态瓶.
主要方法:
- 运用了正统的变化过渡状态理论 (CVTST).
- 计算了潜在能量表面上的最小能量路径.
- (H) 和 (D) 抽取的定位动态瓶.
主要成果:
- 确定了两个不同的动态瓶,对应于H-和D-抽象.
- 在263 K处计算出1.126的KIE,用于d(6) -四甲基乙烯反应.
- 在263 K处发现H/T KIE为1.17的三四甲基乙烯反应.
结论:
- CVTST准确地预测KIEs,并识别反应瓶.
- 同位素效应在单片氧反应的产品分布中起着重要作用.
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