In order to validate the accuracy of the full random forest model the 300 tetramers and 150 hexamers with the lowest predicted λ were selected and the B3LYP λ was computed to compare with the random forest model prediction (Figure ). While the predicted values are not perfect, the low RMSE (0.036 eV) of the prediction versus the calculated λ, indicates that the model is robust and accurate at this new validation set and thus can be used as a first step in finding conjugated materials with better charge transport properties. Interestingly, of the 50 hexamers with the lowest B3LYP λ, 44 oligomers had monomer 47 as one of their monomers, and the hexamer with the lowest B3LYP λ consists of the homo-oligomer of monomer 47, with λ = 0.051 eV (Figure ). This fragment, and related monomers, is frequently used in top organic photovoltaic materials.