We now discuss how molecular HOMO-LUMO gaps and frontier orbital energies change with computational methodology. Summaries of all of the frontier orbital and gap energies discussed in this section are provided in Tables SI, SII, and SIII. Additional eigenvalues are provided in Table . As expected, the HOMO-LUMO gaps of the molecules in vacuum significantly increases (median increase of 6.36 eV) from the GGA-predicted gaps (Figure ). For all molecules except F 2 and H 3 O + , the majority of the gap opening occurs due to a much larger decrease in the HOMO energy (median decrease of 4.96 eV) than the increase in the LUMO energy (median increase of 1.74 eV) (Figure ). Our predicted vacuum GW 0 @GGA gaps are in good agreement with experiment (Table ) and previous studies using similar methodologies. The inclusion of implicit solvation does not significantly affect the HOMO-LUMO gaps nor frontier orbital placements of the molecules at the DFT level (Figure ). This is expected because the contribution to the electrostatic potential from the solvation model is mostly constant / varies slowly in the spatial region of the solute, and therefore contributes an almost rigid shift in the DFT orbital energies of molecules. Similarly, implicit solvation incorporated at the GW level only via modification of the DFT wavefunctions (GW@GGA+SaLSA), produces HOMO/LUMO gaps and energies that are similar to the vacuum GW 0 results.