Imaging CO2 Photodissociation at 157 nm: State-to-State Correlations between CO(ν) and O(3P j=0,1,2)

• Published in: The journal of physical chemistry letters Vol. 1; no. 12; pp. 1861 - 1865
• Main Authors: Chen, Zhichao, Liu, Fuchun, Jiang, Bo, Yang, Xueming, Parker, David H
• Format: Journal Article
• Language: English
• Published: American Chemical Society 17.06.2010
• Subjects: Dynamics, Clusters, Excited States
• ISSN: 1948-7185; 1948-7185
• DOI: 10.1021/jz100356f

The spin-forbidden CO(ν) + O(3P j ) channel produced by 157 nm photodissociation of CO2 was investigated by velocity map imaging. O(3 P) images were measured for the three 3P j spin−orbit states (j = 0, 1, and 2), and the CO vibrational-state distributions that correlate to the O(3P j=0,1,2) spin−orbit product were determined. Nearly all energetically allowed product CO(ν) levels (i.e., ν ≤ 8) are observed, with minor differences in the CO vibrational distributions for the three channels. The angular anisotropy, which also shows minor differences for the three j channels, is found to decrease with increasing CO vibrational excitation, suggesting that the lower vibrational states are produced by photodissociation from a more linear OCO geometry. Fits to the total kinetic energy distributions suggest that the CO rotational energy is relatively cold. The overall results further suggest that the three spin−orbit pathways are not mixed completely in the exit channel.