Stereodynamics Observed in the Reactive Collisions of Low-Energy Ar + with Randomly Oriented O 2

• Published in: The journal of physical chemistry letters 2021-02, Vol.12 (4), p.1346-1351
• Main Authors: Hu, Jie, Wu, Chun-Xiao, Zhi, Yaya, Xie, Jing-Chen, He, Miao-Miao, Tian, Shan Xi
• Format: Article
• Language: English
• ISSN: 1948-7185; 1948-7185
• DOI: 10.1021/acs.jpclett.0c03601

Stereodynamics of the collisional reaction between mutually aligned or oriented reactants has been a striking topic of chemical dynamics for decades. However, the stereodynamic aspects are scarcely revealed for the low-energy collision with a randomly oriented target. Here in the dissociative charge-exchange reaction between randomly oriented O and low-energy Ar , we, using the three-dimensional ion velocity map imaging technique, clearly observe a linear alignment and a nearly isotropic distribution of the O yields along the collision axis. These observations are rationalized with the Doppler kinetic models in which the O bond is assumed to be parallel or unparallel to the collision axis of the large impact parameter collision. The linearly aligned O , as the predominant yield, is produced in the parallel collision, while a rotating O , as the intermediate in the unparallel collision, leads to the isotropic distribution of O .