RMG-database

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https://github.com/ReactionMechanismGenerator/RMG-database/blob/0623bd4f891e7c9e6e669ac0efd5d99a79403429/input/kinetics/libraries/primaryH2O2/reactions.py#L176

entry(
    index = 17,
    label = "OH + HO2 <=> H2O + O2",
    kinetics = Arrhenius(A=(2.14e+06, 'cm^3/(mol*s)', '*|/', 2), n=1.65, Ea = (2180, 'cal/mol'), Tmin=(200, 'K'),
                         Tmax=(2500, 'K')),
    shortDesc = u"""[Konnov2019]""",
    longDesc = u"""Konnov (2019) https://doi.org/10.1016/j.combustflame.2019.01.032, Table 1, Reaction 7""",
)

This reaction is for the triplet O2 channel, but the rate taken from the Konnov paper is for the singlet O2 channel.

From Konnov:

Reaction between OH and HO2 radicals is usually included in kinetic mechanisms as OH + HO2 = H2O + O2. At low temperatures typical for atmospheric chemistry, formation of clusters with water may affect the rate of this reaction [30], which, however, is considered negligible for combustion. Role of recombination channel OH + HO2 + M = HOOOH + M was analyzed by Badenes et al. [31] and found irrelevant at all conditions and pressures up to 400 atm. Recent rate constant measurements at room temperature [32] were attributed to reaction OH + HO2 = H2O + O2 and found in good agreement with previous measurements of, e.g., Keyser [33]. Reaction between OH and HO2 radicals can take place also on singlet potential energy surface forming singlet O2(a¹Δg): (7)OH + HO2 = H2O + O2 (1Δ) It was therefore included in the Konnov [3] mechanism with the rate constant calculated by Gonzalez et al. [34] aiming at analysis of possible role of ozone and reactions of excited species O(1D), OH(2Σ+), and O2(a¹Δg), in hydrogen combustion. Recently, Monge-Palacios and Sarathy [35] repeated ab initio calculations of this reaction at higher level of theory. Their rate constant for the triplet channel is within a factor of two of the rate constant derived by Hong et al. [36] and implemented in the previous [3] and present models, with expression proposed by Burke et al. [37], and with the rates obtained during optimization of hydrogen [4] and syngas [2] mechanisms as illustrated in Fig. S1 of the Supplemental material. The rate constant for the singlet channel, however, was found [35] several orders of magnitude higher than that of Gonzalez et al. [34] as shown in Fig. S2 of the Supplemental material. Nevertheless Monge-Palacios and Sarathy [35] did not find an impact of this reaction on thermal combustion of hydrogen; small difference was seen only in the calculated burning velocities of the mixtures seeded with O3 . This new rate constant of reaction (7) is adopted in the present mechanism.

The paper has a zip of the mechanism as supplementary material and their actual rate for the triplet channel is

HO2+OH=H2O+O2                  7.000E+12      0.0     -1093.0 
    DUPLICATE
HO2+OH=H2O+O2                  4.500E+14      0.0     10930.0 
    DUPLICATE

the file also includes this singlet channel as

HO2+OH=H2O+O2X                 2.140E+06      1.65     2180.0 

if we want to add singlet O2 we could do, but at least we should use the correct rate for the triplet O2.