Towards deep‐blue phosphorescence: molecular design and property prediction of iridium complexes with pyridinylphosphinate ancillary ligand. (30th August 2019)

• Record Type: Journal Article
• Authors: Song, Chongping; Li, Jiaqi; Wang, Zhixiang; Chen, Yanan; Zhao, Fei; Li, Ping; Zhang, Houyu
• Is Part Of: Applied organometallic chemistry. Volume 33:Number 11(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-08-30
• Subjects: deactivation mechanism -- deep‐blue emission -- DFT -- phosphorescent iridium complexes -- pyridinylphosphinate; Organometallic chemistry -- Periodicals; Organometallic compounds -- Periodicals; 547.05
• DOI: 10.1002/aoc.5167
• Languages: English
• ISSNs: 0268-2605

Abstract

Abstract : A series of iridium complexes (1 –5 ), which consist of two 2‐(2, 4‐difluorophenyl)pyridine (dfppy)‐based primary ligands and one pyridinylphosphinate ancillary ligand, have been investigated theoretically for screening highly efficient deep‐blue light‐emitting materials. Compared with the reported dfppy‐based emitter1, the designed iridium complexes3 –5 with the introduction of a stronger electron‐withdrawing (–CN, –CF3, or o‐carborane) group and a bulky electron‐donating (tert‐butyl) group in dfppy ligands can be achieved to display the emission peaks at 443, 442, and 447 nm, respectively. The electronic structures, absorption and emission properties, radiative and nonradiative processes of their excited states, and charge injection and transport properties of the iridium complexes are analyzed in detail. The calculated results show that designed iridium complexes have comparable radiative and nonradiative rate constants with1, and are expected to have similar quantum efficiency with1 . Meanwhile, these designed complexes keep the advantages of the charge transport properties of1, indicating that they are potential iridium complexes for efficient deep‐blue phosphorescence. This work provides more in‐depth understanding the structure–property relationship of dfppy‐based iridium complexes, and shed lights on molecular design for deep‐blue phosphorescent metal complexes. Abstract : A series of iridium complexes, which consist of two dfppy‐type primary ligands and pyridinylphosphinate ancillary ligand, have been investigated by means of quantum chemical calculations for screening the deep‐blue phosphorescent materials. The calculated results show that the designed iridium complexes exhibit deep‐blue phosphorescence emission, and are expected to be have high internal quantum efficiency and balanced electron and hole transport property.