Angular momentum conservation in the O + OH ↔ O2 + H reaction

✍ Scribed by James A. Miller; Stephen J. Klippenstein

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 109 KB
• Volume: 31
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/(sici)1097-4601(1999)31:10<753::aid-jck9>3.0.co;2-m

✦ Synopsis

We have studied the O ϩ OH 4 O 2 ϩ H reaction on Varandas's DMBE IV potential using a variety of statistical methods, all involving the RRKM assumption for the HO complex.

* 2 Comparing our results using microcanonical variational transition-state theory (VT) with those using microcanonical/fixed-J variational transition-state theory (VT-J), we find that the effect of angular momentum conservation on the rate coefficient is imperceptible up to a temperature of about Above angular momentum conservation increasingly re-700 K. 700 K duces the rate coefficient, but only by approximately 21% even at Comparing our VT-5000 K. J calculations with the quasi-classical trajectory (QCT) results of Miller and Garrett [1], we confirm their conclusion that non-RRKM dynamics of the HO complex reduces the rate co-* 2 efficient by about a factor of 2 independent of temperature. Our calculations of the rate (c) k , coefficient for HO formation from O ϩ OH, are in excellent agreement with the QCT results * 2 of Miller and Garrett. Although the differences are not large, we find (c) (c) (c) k Ͼ k Ͼ k Ͼ CVT VT VT-J

where CVT stands for canonical variational transition-state theory.