nity . Bond-additivity corrections are increasingly used in catalysis. Christensen et al. et al. identified that the error is not associated with the OCO backbone but rather with the C=O bond. They obtained a slightly better agreement with the experimental reaction enthalpies when applying corrections of 9.7 kJ mol -1 to H 2 and 14.5 kJ mol -1 for the C=O bond. Additional bond-additivity correction factors were obtained for a range of functionals by Granda-Marulanda et al. for CO 2 , CO, -CH x , -OH, C--O, and (C--O)O. These fragments were hand-picked by experts, which requires chemical intuition and experience. Alternatively, it is possible to use machine-learning techniques like LASSO regression to determine the subgraphs that lead to the best results . Overall, these correction schemes provide chemically intuitive ways to understand the corrections, and in the simplest cases are very straightforward to apply. However, the corrections do not guarantee any specific accuracy of gas-phase reactions and can become rather complex when generalized between different xc functionals.