THE RATE OF METHYL RADICAL DECOMPOSITION AT HIGH-TEMPERATURES AND PRESSURES

Rate constants are calculated for CH3 (+ Ar) reversible arrow CH2 + H (+ Ar) at the limiting low-pressure, the limiting high-pressure, as we ll as the intermediate fall-off ranges. The results show that publishe d experimental rate constants for methyl dissociation correspond to th e fall-off region close to the low-pressure limit. At the low-pressure limit the activation energy is less than the bond dissociation energy , in agreement with experimental results. Forward and backward rate co efficients at the high-pressure limit are compared with other theoreti cal calculations. More theoretical and experimental work is necessary to understand the reverse reaction and its competing reactions, as wel l as the decomposition channel leading to CH + H-2. (C) 1994 John Wile y and Sons, Inc.