High accuracy barrier heights, enthalpies, and rate coefficients for chemical reactions

Quantitative chemical reaction data, including activation energies and reaction rates, are crucial for developing detailed kinetic mechanisms and accurately predicting reaction outcomes. However, such data are often difficult to find, and high-quality datasets are especially rare. Here, we use CCSD(T)-F12a/cc-pVDZ-F12//.B97X-D3/def2-TZVP to obtain high-quality single point calculations for nearly 22,000 unique stable species and transition states. We report the results from these quantum chemistry calculations and extract the barrier heights and reaction enthalpies to create a kinetics dataset of nearly 12,000 gas-phase reactions. These reactions involve H, C, N, and O, contain up to seven heavy atoms, and have cleaned atom-mapped SMILES. Our higher-accuracy coupled-cluster barrier heights differ significantly (RMSE of similar to 5 kcal mol(-1)) relative to those calculated at.B97X-D3/def2-TZVP. We also report accurate transition state theory rate coefficients k(infinity)(T) between 300 K and 2000 K and the corresponding Arrhenius parameters for a subset of rigid reactions. We believe this data will accelerate development of automated and reliable methods for quantitative reaction prediction.

Automated summary

Quantitative chemical reaction data is crucial for understanding reaction kinetics and predicting reaction outcomes, but high-quality data is often difficult to obtain. In this study, we used quantum chemistry calculations to generate a kinetics dataset for nearly 12,000 gas-phase reactions, involving various elements and heavy atoms.