Although the primary goal of this work is the devel- opment of a general formalism needed that integrates quasiparticle calculations with implicit solvation model screening, comparisons to experimental molecular IPs using photoelectron spectroscopy (PES) can be made to validate the accuracy of this approach for occupied states. Measurements of experimental solvated molecular IPs are non-trivial, however, and the development of advanced techniques that increase accuracy are still an ongoing area of research. Additionally, other considerations such as PES peak broadening due to solvent and summarizes the available experimental IPs and the corresponding values predicted by the current approach. The results show that this methodology predicts reasonably accurate solvated IPs given existing measurement uncertainty. This suggests the SaLSA implicit solvation model may capture the ensemble solvent interaction with solute HOMOs, potentially reducing the need for full explicit solvation and requiring a less extensive degree of statistical sampling. Similarly, although the band gap of liquid water has been the subject of several investigations, no clear consensus exists on the exact gap. Briefly, an oft-cited experimental gap estimate is 8.7 ± 0.5 eV with a more recent estimate of 9.0 ± 0.2 eV, while the computational gap has ranged from 7.8 to 10.5 eV. Our predicted H 2 O GW 0 @GGA+SaLSA+χ lq HOMO-LUMO gap of 8.669 eV is similar to these values. The accuracy of our predicted solvated IPs is consistent with the observation that the GW approximation performs surprisingly well in predicting accurate molecular IPs in vacuum given the relative simplicity of the method. We also note that because our approach considers off-diagonal and frequency-dependent elements in the solvent polarizability (Figure ), it is consistent with the well-known finding that the GW approximation is most accurate when both local field and dynamical effects are included. Despite the accuracy of the predicted IPs, it is important to note that the predicted GW 0 @GGA+SaLSA+χ lq LUMO values all lie between approximately -2 and -3 eV, when the solvated water LUMO has been previously predicted to be -0.8 -0.1 eV by beyond-DFT computational studies using fully explicit water models. This discrepancy could originate from one or more sources, including 1) the PBE starting point for the unoccupied states may be particularly inaccurate, 2) unoccupied states are significantly influenced by interactions with the explicit water molecules included in previous studies, and/or 3) the SaLSA implicit solvation model is known to poorly describe the asymmetry in solvation of cations and anions and thus could be expected to less accurately predict an N+1 particle property such as the EA (=ϵ LU M O ). Future work elucidating the impact of nearby explicit water molecules, functional starting point, and improvements in implicit solvation models are currently ongoing. Nevertheless, we believe that the approach described here will help facilitate beyond-DFT modeling of solvated molecular and electrocatalytic systems within the joint-DFT framework and only continue to improve as advancements in solvation models and DFT functionals are made.