One simple yet effective remedy to DFT convergence issues in large molecules is to apply dielectric screening via a polarizable continuum model (PCM), first introduced by Atony and Grimme 2, 10 and later investigated by Payne et al. It was found that the PCM field could open the HOMO-LUMO gap and avoid the frequent mixture of virtual and occupied orbitals between SCF iterations. However, Kohn-Sham (KS) orbital energies are little affected by the PCM reaction field in other contexts, such as the optimal tuning of long-range corrected functionals in PCM. The origin of PCM's effects on SCF convergence improvement and DE reduction has not been thoroughly investigated for large molecules. It is unclear whether PCM can be used as a universal SCF accelerator or only effective for specific large molecules. How the electronic structure of the large molecules can be impacted by the PCM field has not been scrutinized either.