The solvatochromic effect is studied in different solvents with varied polarity to explore the electronic structures, by taking S-BNPCN-o-CP and S-BNPCN-p-CP as examples. The PL peaks of S-BNPCN-o-CP and S-BNPCN-p-CP are red-shifted from 376 and 370 nm in low-polar hexane to 465 and 474 nm in high-polar acetonitrile (Supplementary Fig. ), respectively, due to enhanced ICT effect. Linear relationships between Stokes shift (va -vf) and solvent polarity (f) fitted by the Lippert-Mataga model (Supplementary Fig. , Supplementary Table and) suggest that they have a quasi-equivalent hybridization character originating from a balanced intercrossed coupling between locally excited and charge transfer states, which is beneficial for achieving high emission efficiency and high exciton utilization simultaneously .