Angular momentum conservation in multichannel unimolecular reactions
Angular momentum conservation in multichannel unimolecular reactions
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多通道单分子反应中的角动量守恒
DOI：
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发表时间：
1988
期刊：
影响因子：
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通讯作者：
R. Gilbert
中科院分区：
文献类型：
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作者：
Sean C. Smith;R. Gilbert
最近开发的单分子和重组反应的主方程的解决方案进行了扩展，以提供新的手段，将角动量（J）守恒的下降制度的多通道反应。典型的多通道单分子解离反应（1-碘丙烷的热解离）的计算压力依赖性表明，如果通道之一具有惯性矩（I t）与母体分子（I）显著不同的过渡态（例如，“简单裂变”型），忽略角动量守恒导致预测的分支比在较低压力下严重错误。具体而言，如果I <$> I，则速率系数被低估，而如果I <$< I，则速率系数被高估。
A recently developed solution of the master equation for unimolecular and recombination reactions is extended to give new means for incorporating angular momentum (J) conservation in the fall-off regime for multichannel reactions. The calculated pressure dependence of a typical multichannel unimolecular dissociation reaction (thermal dissociation of 1-iodopropane) shows that if one of the channels has a transition state with a moment of inertia (I†) significantly different from that of the parent molecule (I) (e.g., a “simple-fission” type), neglect of angular momentum conservation causes the predicted branching ratio to be grossly in error at lower pressures. Specifically, if I† > I the rate coefficient is underestimated whereas if I† < I the rate coefficient is overestimated.