Mechanism of the OH+CH2CO reaction

Potential energy surface for the reaction of hydroxyl radical with molecula r ketene has been studied using the ab initio G3(MP2) method. Three distinc t reaction mechanisms, namely direct hydrogen abstraction, olefinic carbon addition, and carbonyl carbon addition, are revealed. A total of seven prim ary product channels, H2O + HCCO, CO + CH2OH, HCO + CH2O, H + (HCO)(2), H CH(OH)CO, CO2 + CH3 and CO + CH3O, including the consideration of six inte rmediates, are detailed. Moreover, the branching ratios are calculated usin g the RRKM-TST procedure. The findings in this theoretical study are in agr eement with the available experimental measurements. The calculations show that at higher temperatures the major product channel is direct hydrogen ab straction leading to H2O and HCCO, whereas the formation of CO and CH2OH do minates the title reaction at lower temperatures.