For E red. and pK a , the data set of chemical properties contains 49278 samples, while the structure-based one contains 49271 samples altogether. There are seven fewer samples in the second data set because of the molecules' rotational symmetry. The SMILES duplicate check found them, and they were removed. Additionally, the relevant information of QH 2 , QH + 2 , QH -, and QH compounds was stored for predicting E 0 . There are 32865 samples in this dataset.