ReactionMechanismGenerator / ReactionMechanismGenerator/RMG-database

Ea in ROOH_sec;C_rad/H/NonDeC - Amrit Jalan's Thesis - Is the entry in the database correct?

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Description

The reaction ROOH + R. = ROO. + RH has an exact match in the RMG database, indicated with '[AJ]'.
It was suggested that this was calculated by Amrit Jalan - however reading his thesis, unless I am making a mistake, a positive activation energy is suggested while the database contains a negative activation energy? (Thesis link: https://dspace.mit.edu/handle/1721.1/91059 - page 195)

Entry in the database (same applies for the entry above with ROOH_pri):

entry(
    index = 551,
    label = "ROOH_sec;C_rad/H/NonDeC",
    kinetics = ArrheniusEP(
        A = (2.51e-11, 'cm^3/(mol*s)'),
        n = 6.77,
        alpha = 0,
        E0 = (-8.6, 'kcal/mol'),
        Tmin = (500, 'K'),
        Tmax = (1000, 'K'),
    ),
    rank = 3,
    shortDesc = u"""[AJ]CBS-QB3 calculations with 1DHR corrections, reverse rates computed using DFT_QCI_thermo""",
)

And in Jalan's Thesis (page 195) I find:

Table 6.1: Predicted Arrhenius parameters (Units: mol, cm 3 , sec, kcal/mol) for
CH3OO* + RH* H-abstraction reactions with R=CH3CH2CH2_, CH3C_(OOH)CH3,
CH3COCH2_, CH3CH2C_O.

Reaction A n Ea
CH3CH2CH3 -> CH300H + CH3CH_CH3 1.3 x10-8 6.2 8.5
CH3CH(OOH)CH 3 -> CH3C(O)CH3 + *OH + CH300H 1.1 x10-13 7.2 2.9
CH3C(O)CH3 -> CH300H + *CH2C(O)CH3 4.4 x10-12 7.1 8.9
CH3CH2CHO -> CH300H + CH3CH2C_O 1.9 x10-3 4.5 4.4

The units for A are sec- 1 for unimolecular reactions and in cm 3 mol-1 sec-1 for
bimolecular reactions, with Ea in kcal/mol. The rate coefficient is
k = A(T/1[K])" exp(-Ea/RT).

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Research direction

Inspect the database entry for index 551, labeled "ROOH_sec;C_rad/H/NonDeC", and compare its Arrhenius parameters with page 195 of Amrit Jalan's thesis. Verify whether the negative E0 and associated A and n values are correct for the stated reaction, then document and correct the entry if the comparison confirms an error.

Written by the indexing model from the issue text.

Assessment

Domain
databases
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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