Quasiclassical trajectory calculations of the thermal rate coefficient for the oxygen atom + hydroxyl .fwdarw. oxygen + hydrogen atom reaction on realistic double many-body expansion potential energy surfaces for ground-state hydroperoxy

Quasi-classical trajectory calculations of the thermal rate coefficient for the title reaction have been carried out over the temperature 250 5 T 5 2500 K by using two recently reported DMBE potential energy surfaces for the ground state of the hydroperoxyl . The results are compared with each other and with experiment. The agreement is god. Our results support previous calculations by Miller on the Melius-Blint potential energy surface in that nonstatistical ‘recrossing” effects are important. For the DMBE I1 (DMBE 111) potential energy surface, these nonstatistical corrections are found to increase a factor of about 1.2 (1.4) at 250 K to about 2.1 (2.5) at 2500 K. However, they are considerably smaller than the corrections reported by Miller (factors of about 2.2 and 3.3 at the above temperatures). Although due, of , to topographical differences between the DMBE and Melius-Blint potential energy surfaces, such discrepancy stems from the different definitions used for H02* complex in the simple chemical model 0 + OH e H02* -+ 0 2 + H.