Large-scale thermochemistry calculations for combustion models

• Large scale thermodynamic database using ab-initio calculations Accurate data for chemical kinetic models Homogeneous promote advanced machine-learning Differences with incumbent values warrant revisiting kinetics Effect on IDT observed new thermochemical properties species are of vital importance in combustion chemistry research. Group additivity approaches widely used to generate thermochemistry models, but this approach has limited accuracy. Following previous studies by the community, we performed electronic structure obtain reliable a large set molecules taken from well-established model. The developed consists 1340 that contain up 18 and 5 carbon oxygen atoms, respectively. M06-2X/aug-cc-pVTZ level theory was geometry optimizations, vibrational frequency calculations, dihedral angle scans. potential energy different further refined composite methods, G3 method atomization reaction selected calculate enthalpy formation at 0 K. This information then statistical thermodynamics standard enthalpies entropy, as well heat capacities temperatures. Our exhibits good agreement existing literature, verifying accuracy our approach. Comparisons against group (GA) also presented. quantities study can be improve training GA or machine learning models. impact dataset is illustrated examining variation ignition delay times updated values.