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Title: Improved deep-red phosphorescence in cyclometalated iridium complexes via ancillary ligand modification
In this work, we describe bis-cyclometalated iridium complexes with efficient deep-red luminescence. Two different cyclometalating (C^N) ligands-1-phenylisoquinoline (piq) and 2-(2-pyridyl)benzothiophene (btp)-are used with five strong π-donating ancillary ligands (L^X) to furnish a suite of nine new complexes with the general formula Ir(C^N) 2 (L^X). Improvements in deep-red photoluminescence quantum yields were accomplished by the incorporation of sterically encumbering substituents onto the ancillary ligand, which can enhance the radiative rate constant ( k r ) and/or reduce the non-radiative rate constant ( k nr ). Five of the complexes were characterized by X-ray crystallography, and all of them were investigated by in-depth spectroscopic and electrochemical measurements.  more » « less
Award ID(s):
1846831
PAR ID:
10317922
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Inorganic Chemistry Frontiers
Volume:
7
Issue:
6
ISSN:
2052-1553
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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