Photodissociation dynamics of acetaldehyde at 267 nm: A computational study of the CO‐forming channels.

A recent experiment on the 267 nm photolysis of gaseous acetaldehyde reveals that the molecular products (CO + CH4) present product state distributions with computation –experiment discrepancy. This work aims to provide solution to such issue. The direct dynamics simulation of classical trajectories and the generalized multi‐center impulsive model (GMCIM) are both utilized to predict the product state distributions of CO and CH4 from 267 nm photolysis of acetaldehyde. Comparison with the experimental observation provides an assessment of the conventional approach of minimum energy path within the framework of three‐center transition state (TS) and CH3‐roaming pathways. The result shows that the high‐speed products observed in experiment are likely formed via the three‐center TS pathway. The reasons that lead to the discrepancy between computation and experiments in previous studies are also investigated. A better agreement between computational and state‐resolved experimental results can be achieved by selecting specific internal states of CO product from the computational data. [ABSTRACT FROM AUTHOR]