A CGA-ONIOM-DFT framework for accurate and efficient determination of thermodynamics and Kinetics: Case study of cyclopentane reaction with hydroxyl radical

[Display omitted] •The CGA-ONIOM method was extended for rate constant calculation to prove it accuracy and efficiency in determining the thermodynamics and kinetics of large combustion reaction system.•A hybrid CGA-ONIOM-DFT framework was proposed to approach accurate kinetics of large reaction system with loose transition state at affordable cost.•The CGA-ONIOM-DFT framework was shown to be more efficient for larger reaction system. Accurate and efficient determination of thermodynamics and kinetics is long pursued but hindered by electronic energy calculations due to very high computational cost. In this work, we propose a Cascaded Group Additivity (CGA)-ONIOM-DFT framework targeting fast thermodynamic and kinetic predictions. We studied the reaction of cyclopentane with OH radical as a proof-of-principle demonstration. The CGA-ONIOM method accurately constructed the potential energy surface with a mean unsigned error of 0.20 kcal∙mol-1 compared to the full-level CCSD(T)/CBS results. The calculated rate constants agree well with the experimental data, suggesting the feasibility of using the CGA-ONIOM-DFT framework for combustion chemical kinetics.