As seen in Table , switching to EHF embedding in this system significantly improves the performance of ECI, leading to RMSD values of around 0.04 eV (triplets) or 0.1 eV (singlets). This is in contrast to G 4 , where ESP embedding was already sufficient and EHF embedding did not significantly improve the results. Particularly, at ECIS+EHF level of theory, all eight excited singlet states are now qualitatively correct in terms of degeneracy pattern, energy splitting, and oscillator strengths. The oscillator strengths of states S 5 -S 8 agree very well with the reference, although the ones for S 1 -S 4 are still too low. As seen from the ECI vectors in Table , expectedly EHF embedding completely eliminates any excitonic correlation in the ground state, as the E 0 diagnostic is 1.000. This reduction in excitonic correlation is due to the self-consistency of the site states, which translates into effectively vanishing elements in the GS-LE couplings according to Brillouin's theorem.