Theoretical study of the high intersystem spin crossing (ISC) ability of a series of iridium complexes with low efficiency roll‐off properties.

A series of heteroleptic cyclometalated Ir(III) complexes for OLEDs application have been investigated theoretically to explore their electronic structures and spectroscopic properties. The geometries, electronic structures, lowest‐lying singlet absorptions, and triplet emissions of (pdbi)2Ir(acac), (F‐pdbi)2Ir(acac), (pdbi)2Ir(dpis), (F‐pdbi)2Ir(dpis), (pdbi)2Ir(tpip), and (F‐pdbi)2Ir(tpip) were investigated with density function theory (DFT) and time‐dependent density functional theory (TD‐DFT), where pdbi denotes 1‐(4‐fluorophenyl)‐5‐methyl‐3‐phenyl‐2,3‐dihydro‐1H‐1,3‐benzodiazole, acac denotes acetylacetonate, dpis denotes diphenylimidodisilicate, and tpip denotes tetraphenylimido‐diphosphinate. In addition, we analyzed the spin‐orbit coupling constant of these six complexes, and the results showed that the six complexes have a high ability of interlinear scampering. We hope this research can serve as a reference for practical experimental synthesis aspects. [ABSTRACT FROM AUTHOR]