Highly luminescent palladium(ii) complexes with sub-millisecond blue to green phosphorescent excited states. Photocatalysis and highly efficient PSF-OLEDs.

ABSTRACT: Palladium(ii) complexes supported by tetradentate [N^C^C^N] and [O^N^C^N] ligand systems display sky blue to red phosphorescence with emission quantum yields and emission lifetimes up to 0.64 and 272 μs, respectively. Femtosecond time-resolved fluorescence (fs-TRF) measurements on these Pd(ii) complexes reveal a fast intersystem crossing from singlet to triplet manifolds with time constants of 0.6-21 ps. DFT/TDDFT calculations revealed that, as a result of the spiro-fluorene and bridging tertiary amine units of the ligands, the T₁ excited state is more ligand-localized and has smaller structural distortion, leading to slower non-radiative decay as well as radiative decay of T₁ → S₀ transition and thereby highly emissive, long-lived triplet excited states. T

SUBMITTER: Chow PK 

PROVIDER: S-EPMC6024183 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature