Hot Vibrational States in a High-Performance Multiple Resonance Emitter and the Effect of Excimer Quenching on Organic Light-Emitting Diodes.

ABSTRACT: The photophysics of multiple resonance thermally activated delayed fluorescence molecule ν-DABNA is described. We show coupling of a 285 cm^-1 stretching/scissoring vibrational mode of peripheral phenyl rings to the S₁ state, which dictates the ultimate emission full-width at half maximum. However, a separate high amplitude mode, 945 cm^-1 of the N-biphenyl units, mediates the reverse intersystem crossing (rISC) mechanism. Concentration-dependent studies in solution and solid state reveal a second emission band that increases nonlinearly with concentration, independent of the environment assigned to excimer emission. Even at concentrations well below those used in devices, the excimer contribution affects performance. Using different solvents and solid

SUBMITTER: Stavrou K 

PROVIDER: S-EPMC8023512 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature