Li Hongwei, Kamasah Alexander, Suits Arthur G
Department of Chemistry, University of Missouri Columbia, MO 65211, USA.
Phys Chem Chem Phys. 2019 Jul 14;21(26):14186-14194. doi: 10.1039/c8cp06351f. Epub 2018 Nov 21.
The crossed beam reaction dynamics of ground state O(P) atoms with propanol isomers (1-propanol and 2-propanol) have been studied for the first time using the velocity map imaging technique. The hydroxypropyl radical products, generated from H-abstraction of the secondary and tertiary C-H groups of propanol isomers, were detected via single photon ionization at 157 nm under single collision conditions with collision energies of 8 and 10 kcal mol. Direct rebound dynamics were suggested by the angular distributions, which show overall sideways-backward scattering but more pronounced backward scattering for both isomer reactions under all collision energies studied here. All the translational energy distributions peak at low energy, on average 20-40% of the total available energy. This indicates high internal excitation in the products that is treated by various models of energy release. We infer that most of the total available energy is partitioned into rotational excitation due to the long-rang dipole-dipole interaction between the dipolar OH and hydroxypropyl radicals.
首次使用速度成像技术研究了基态O(P)原子与丙醇异构体（1-丙醇和2-丙醇）的交叉束反应动力学。通过在157 nm处的单光子电离，在单次碰撞条件下、碰撞能量为8和10 kcal/mol时，检测到由丙醇异构体仲碳和叔碳C-H基团的H抽取产生的羟丙基自由基产物。角分布表明存在直接反弹动力学，在本文研究的所有碰撞能量下，两种异构体反应均显示出整体的侧向-向后散射，但向后散射更为明显。所有平动能分布在低能量处达到峰值，平均占总可用能量的20%-40%。这表明产物中存在高内部激发，这由各种能量释放模型来处理。我们推断，由于偶极OH和羟丙基自由基之间的长程偶极-偶极相互作用，大部分总可用能量被分配到转动激发中。
