Specifically, the training sets for the ML models considered in this study were derived from the existing PubChemQC (PCQC) and QM-symex databases. For concision, we will use the (functional/basis set) notation to describe the level of theory used in calculations. PCQC includes the first 10 singlet excited state energies (S 1-10 ) for 3.5M molecules computed using B3LYP/6-31G(d) for ground state optimization and B3LYP/6-31+G(d) for excitation. Similarly, QM-symex computes both S 1-10 and the first 10 triplet excited state energies (T 1-10 ) for 173k molecules using B3LYP/6-31G(2df,p) for ground state optimization and B3LYP/6-31G for excitation.