AutoMech

Large-Scale Automated Mechanism Modeling

Automated identification and calculation of prompt effects in kinetic mechanisms using statistical models

The kinetics of prompt dissociation involves rovibrationally excited species (generally formed by exothermic reactions) which may dissociate or isomerize prior to thermalization via collisions with the bath gas. Treating such rovibrationally excited species (so-called “hot” species) with standard kinetic phenomenology may result in incorrect macroscopic representation of their reactivity. This work presents the first fully automated methodology for the calculation of prompt effects of a chosen species in a kinetic mechanism, including (i) reaction selection; (ii) theoretical calculation of rate constants and prompt branching fractions; and (iii) final rate constant fitting. The energy partition between hot fragments is estimated using a variety of statistical models, including a new physically sound microcanonical statistical model based on the rovibrational density of states of the fragments[...]

AutoMech v0.1.2

Elliott, S. N.; Moore, K. B.; Copan, A. V.; Georgievskii, Y.; Keceli, M.; Somers, K. P.; Ghosh, M. K.; Curran, H. J.; Klippenstein, S. J.; Systematically Derived Thermodynamic Properties for Alkane Oxidation (Combust. Flame, 2022, Accepted)doi:10.1021/jacs.0c11677.

Ghosh, M. K.; Panigrahy, S.; Dong, S.; Elliott, S. N.; Klippenstein, S. J.; Curran, H. J.; The Influence of Thermochemistry on the Reactivity of Propane, the Pentane Isomers and $n$-heptane in the Low Temperature Regime. Proc. Combust. Inst., 2022, (Preprint)

S. N. Elliott, K. B. Moore, A. V. Copan, M. Keceli, C. Cavallotti, Y. Georgievskii, S. F. Schaefer, and S. J. Klippenstein. Automated theoretical chemical kinetics: predicting the kinetics for the initial stages of pyrolysis. Proc. Combust. Inst., 38:375–384, 2021. doi:10.1016/j.proci.2020.06.019.
D. P. Zaleski, R. Sivaramakrishnan, H. R. Weller, N. A. Seifert, D. H. Bross, B. Ruscic, K. B. Moore, S. N. Elliott, A. V. Copan, L. B. Harding, S. J. Klippenstein, R. W. Field, and K. Prozument. Substitution reactions in the pyrolysis of acetone revealed through a modeling, experiment, theory paradigm. J. Am. Chem. Soc., 143:3124–3142, 2021. doi:10.1021/jacs.0c11677.

S. N. Elliott, K. B. Moore, A. V. Copan, M. Keceli, C. Cavallotti, Y. Georgievskii, S. F. Schaefer, and S. J. Klippenstein. Automated theoretical chemical kinetics: predicting the kinetics for the initial stages of pyrolysis. Proc. Combust. Inst., 38:375–384, 2021. doi:10.1016/j.proci.2020.06.019.
D. P. Zaleski, R. Sivaramakrishnan, H. R. Weller, N. A. Seifert, D. H. Bross, B. Ruscic, K. B. Moore, S. N. Elliott, A. V. Copan, L. B. Harding, S. J. Klippenstein, R. W. Field, and K. Prozument. Substitution reactions in the pyrolysis of acetone revealed through a modeling, experiment, theory paradigm. J. Am. Chem. Soc., 143:3124–3142, 2021. doi:10.1021/jacs.0c11677.

QTC (AutoMech Prototype)

M. Keceli, S. N. Elliott, Y. P. Li, M. S. Johnson, C. Cavallotti, Y. Georgievskii, W. H. Green, M. Melucchi, J. M. Wozniak, A. W. Jasper, S. J. Klippenstein. Automated computational thermochemistry for butane oxidation: A prelude to predictive automated combustion kinetics. Proc. Combust. Inst., 37:363-371, 2019. doi:10.1016/j.proci.2018.07.113.

EStokTP

C. Cavallotti, C., M. Pelucchi, Y. Georgievskii, S. J. Klippenstein. EStokTP: electronic structure to temperature-and pressure-dependent rate constants—a code for automatically predicting the thermal kinetics of reactions. J. Chem. Theory Comput., 15(2):1122-1145, 2018. doi:10.1021/acs.jctc.8b00701.