US EPA

1113066 

Journal Article 

Multichannel RRKM-TST and CVT Rate Constant Calculations for Reactions of CH2OH or CH3O with HO2 

Mousavipour, SH; Homayoon, Z 

2011 

1 

Journal of Physical Chemistry A
ISSN: 1089-5639
EISSN: 1520-5215 

115 

15 

3291-3300 

English 

21434683 

10.1021/jp112081r 

The kinetics and mechanism of the gas-phase reactions between hydroxy methyl radical (CH(2)OH) or methoxy radical (CH(3)O) with hydroproxy radical (HO(2)) have been theoretically investigated on their lowest singlet and triplet surfaces. Our investigations indicate the presence of one deep potential well on the singlet surface of each of these systems that play crucial roles on their kinetics. We have shown that the major products of CH(2)OH + HO(2) system are HCOOH, H(2)O, H(2)O(2), and CH(2)O and for CH(3)O + HO(2) system are CH(3)OH and O(2). Multichannel RRKM-TST calculations have been carried out to calculate the individual rate constants for those channels proceed through the formation of activated adducts on the singlet surfaces. The rate constants for direct hydrogen abstraction reactions on the singlet and triplet surfaces were calculated by means of direct-dynamics canonical variational transition-state theory with small curvature approximation for the tunneling.