Mesomerism induced temperature-dependent multicomponent phosphorescence emissions in ClBDBT

Quantum mechanics/molecular mechanics (QM/MM) and molecular dynamics (MD) methods were applied to systematically investigate the temperature-dependent phosphorescence emission of dibenzo[b,d]thiophen-2-yl(4-chlorophenyl)methanone (ClBDBT) and its derivatives. The calculated temperature-dependent spectra on the lowest triplet state (T1) are in good agreement with the experimental observations, which means that the two-component white light emission should stem from the T1 state. The further MD simulations demonstrate the existence of two mesomerism structures at room temperature which can emit two lights simultaneously. The multi-component light emissions induced by mesomerism structures have advantages in balancing the distribution of excitons which could be beneficial to obtain pure white light along with stable Commission Internationale de l'eclairage (CIE) coordinates. We hope this mesomerism concept can be further used to design new white light emitters based on room-temperature phosphorescence. The existence of two mesomerism structures could emit two phosphorescence bands simultaneously and well balance the distribution of excitons for multicomponent emissions.

Automated summary

Quantum mechanics/molecular mechanics (QM/MM) and molecular dynamics (MD) methods were used to investigate the temperature-dependent phosphorescence emission of ClBDBT and its derivatives. The calculated spectra on the T1 state matched well with experimental observations, indicating that the white light emission arises from the T1 state. MD simulations further revealed the presence of two mesomerism structures at room temperature, which can emit dual light emissions.