Dynamics and mechanisms of CO production from the reactions of CH2 radicals with O(3P) and O2

Abstract

A cw CO laser has been used to probe the complete CO vibrational energy distributions in the reactions of CH2 radicals with O(3P) and O2 (3∑−g. The CO formed from the reaction with the atom was concluded to be produced via two equally important channels, O+CH2→CO+H2→CO+2H,, with an average vibrational energy of 19 kcal/mole, and an approximate vibrational temperature of ≈104K (for v≤12), which is sufficient to account for previously observed CO stimulated emission from O(3P)+CH2. The population inversion derives mainly from the molecular hydrogen elimination channel. In the reaction of CH2 with molecular oxygen, the CO formed is believed to be produced from both a molecular elimination path giving H2O+CO and from two possible atomic or radical production processes, yielding H+CO+OH. We find from analysis of the CO product vibrational energy distribution that 30% of the CO formed is produced via the former path, and 70% is formed from the latter path. This information is important to the detailed kinetic modeling of acetylene and other hydrocarbon combustion systems.