This study is based on a set of 822 molecules, 711 of which come from a dataset gathered by Hutchison et al. An additional 91 molecules are hydrocarbons derived from the Hutchison molecules by substituting heteroatoms with carbon atoms. Twenty molecules are taken from the work of Grayson et al. The Grayson dataset molecules are mostly organic catalysts with hydrogen-bonding donating characteristics. Additionally, a small number of molecules, including three radical structures, come directly from literature. The structures are listed in the SI. Conformational searching calculations were conducted on the 822 molecules in MacroModel (v11.7) 15 with Merck Molecular Force Field (MMFF) . Conformers with energies more than 10 kcal mol -1 above the global minimum were omitted. For radicals, ground state pseudo structures were used for conformational searching calculations. Out of the initial pool of 822 molecules, a subset of 150 was selected for the construction of the DFT data set (Figure ; Table ). The 150 molecules include the 20 Grayson dataset molecules and 3 radical molecules. The remaining 127 molecules were randomly selected. Out of the 150 molecules, 22 are charged, with 2 of them being zwitterions. For this subset, we re-optimized all the FF structures from the conformational searching calculations at the DFT level. DFT optimizations were performed with Gaussian 16 (Revision B.01). Here, the B3LYP-D3/6-31G(d) level of theory was chosen for the optimization and frequency calculations. Single-point energy calculations were conducted at the ωB97X-D/6-311G(d,p) level of theory. Unless specified, the 'DFT level' in the text below refers to this level of theory. The 150 molecules are diverse in terms of molecular size and flexibility. The total number of conformers ranges from 2 to 321 and the average number of atoms is 44. About 15 % of the re-optimized structures were found to be duplicates.