Next, we show the distribution of the error in reaction energies with respect to G4MP2 reaction energies of different methods in Figure . It is interesting, albeit being expected, that the errors of the DFT functionals with the TZP and the DZP basis sets are similar and significantly small. The distribution of error in XTB reaction energies is similar to that of the DFT level with SZ basis set. Also, the error in energy distribution is mostly symmetric and of Gaussian type. This indicates that in any situation even though there can be large errors in atomization energies, the reaction energies mostly follows a normal distribution with majority of reactions in a relatively small error scale. This type of behaviour is known and expected since for a reaction, cancellation of errors occurs. Therefore, the errors in reaction energies becomes lower and sink to a scale which is much smaller than atomization energies.