Gaussian 16 was used for all DFT calculations with a default ultra-fine grid for all numerical integration. The primary database of redox potentials was built using the M06-2x/def2-TZVP level of theory by separately optimizing the neutral, oxidized, and reduced radical species. The calculations were performed using the SMD solvation model with a water solvent at 298K. The same initial structures were used for all three calculations and were taken from previous calculations performed in the gas phase. Iodine-based molecules in the experimental redox benchmark were optimized with the LAN2DZ basis set in combination with 6-31G(d,p) and 6-31g+(d,p). An automated workflow was developed to check optimizations for convergence by ensuring the absence of imaginary vibrational frequencies and that all bond lengths remained within 0.4 Å of the sum of their covalent radii. Additionally, molecules were inspected to see whether new bonds were formed during optimization, as this often led to difficult-topredict redox potentials. Atom adjacency matrices were used to determine if any two atoms were closer than 1.3 times the sum of their covalent radii, and these molecules were removed from the training dataset. This primarily occurred during oxidation, as 8,566 oxidized molecules, 602 reduced molecules, and 177 neutral radicals were removed from the database in this fashion.