Photodissociation of CH3CHO at 248 nm by time-resolved Fourier-transform infrared emission spectroscopy: verification of roaming and triple fragmentation

By using time-resolved Fourier-transform infrared emission spectroscopy, the HCO fragment dissociated from acetaldehyde (CH3CHO) at 248 nm is found to partially decompose to H and CO. The fragment yields are enhanced by the Ar addition that facilitates the collision-induced internal conversion. The...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of chemical physics 2014-02, Vol.140 (6), p.064313-064313
Main Authors: Hung, Kai-Chan, Tsai, Po-Yu, Li, Hou-Kuan, Lin, King-Chuen
Format: Article
Language:English
Subjects:
Acetaldehyde
Emission spectroscopy
Fourier transforms
Fragmentation
Infrared spectroscopy
Internal conversion
Photodissociation
Population distribution
Spectrum analysis
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:By using time-resolved Fourier-transform infrared emission spectroscopy, the HCO fragment dissociated from acetaldehyde (CH3CHO) at 248 nm is found to partially decompose to H and CO. The fragment yields are enhanced by the Ar addition that facilitates the collision-induced internal conversion. The channels to CH2CO + H2 and CH3CO + H are not detected significantly. The rotational population distribution of CO, after removing the Ar collision effect, shows a bimodal feature comprising both low- and high-rotational (J) components, sharing a fraction of 19% and 81%, respectively, for the vibrational state v = 1. The low-J component is ascribed to both roaming pathway and triple fragmentation. They are determined to have a branching ratio of 0.06, respectively, relative to the whole v = 1 population. The CO roaming is accompanied by a highly vibrational population of CH4 that yields a vibrational bimodality.
ISSN:0021-9606
1089-7690
DOI:10.1063/1.4862266