To estimate the accuracy of the DFPT calculations, the respective mean polarizabilities were compared with the values documented in the QM7b database . This comparison ensures an accurate assessment of the prediction error due to the following two reasons: i) there is a large overlap between the structures in the QM7b and QM7-X databases, and ii) QM7b provides highly accurate α values obtained at the linear-response coupled cluster singles and doubles (LR-CCSD) level of theory . Then, we computed the polarizabilities of 300 randomly selected structures of QM7b employing the same DFPT computational setup described above. The selected level predicts α with a mean average error of 1.9 % with a standard deviation of 1.1 % (cf. Fig. S 1 of the ESI † ). This accuracy is higher with respect to average DFT methods which produce mean average errors between 2.5 % and 3.8 % , underlining the benefits of calculating polarizabilities using the PBE0 functional. Polarizability anisrotropy is predicted with a mean average error of 10.2 % with a standard deviation of 5.1 %, which is in line with previously reported values . In general, the mean polarizability is slightly underestimated, whereas the anisotropy is almost always overestimated by PBE0.