In our automated DFT-calculation/descriptor extraction workflow, several validation checks were performed, including post-processing using the AQME software to address convergence issues (vide supra) and connectivity validation to exclude intrinsically unstable compounds. Similar to traditional Hammett substituent constants, which only included metaand parasubstituted benzenes to avoid influences of steric effects of ortho substituents, we excluded σHet values for all heteroaryl groups with another substituent at an ortho position and those with A 1,3 -type interactions (e.g., 4-benzothiophenyl with another substituent at the 3position). These procedures ensure that the reported σHet values describe electronic properties only.