Open AccessTuning the Photophysical and Excited State Properties of Phosphorescent Iridium(III) Complexes by Polycyclic Unit Substitution
Author(s) -
Wu Cuicui,
Li Qiuxia,
Zhang Xinghua,
Shi Chao,
Li Gang,
Wang Mingjie,
Li Kang,
Yuan Aihua
Publication year - 2019
Publication title -
chemistryopen
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 29
ISSN - 2191-1363
DOI - 10.1002/open.201900041
Subject(s) - phosphorescence , iridium , excited state , photochemistry , ligand (biochemistry) , chemistry , luminescence , substituent , materials science , fluorescence , stereochemistry , atomic physics , optoelectronics , organic chemistry , physics , biochemistry , receptor , catalysis , quantum mechanics
Two novel N‐embedded polycyclic units functionalized phosphorescent iridium(III) complexes ( Ir‐1 and Ir‐2 ) with substituents in different positions have been prepared. Complex Ir‐1 bearing the substituent at the 3‐position shows a distinct blue shift single‐peak emission (524 nm) with a higher luminescence efficiency (Φ PL =42 %) and shorter emission lifetime (τ=282 ns) by comparison with 4‐position substitution based complex Ir‐2 (Φ PL =23 %, τ=562 ns), which exhibits a dual‐peak emission (564 nm and 602 nm), and phosphorescence color can be tuned from green to yellow. In addition, DFT calculations demonstrate that unusual ligand‐to‐metal charge transfer ( 3 LMCT) excited state property can be found in Ir‐2 , which is in contrast to metal‐to‐ligand charge transfer ( 3 MLCT) excited state character in Ir‐1 . This result can be attribute to strong electron‐donating character and 4‐position substitution effect of the unit.