| Title |
Revealing resonance effects and intramolecular dipole interactions in the positional isomers of benzonitrile-core thermally activated delayed fluorescence materials / |
| Authors |
Kukhta, Nadzeya ; Higginbotham, Heather F ; Matulaitis, Tomas ; Danos, Andrew ; Bismillah, Aisha N ; Haase, Nils ; Etherington, Marc K ; Yufit, Dmitry S ; McGonigal, Paul R ; Grazulevicius, Juozas Vidas ; Monkman, Andrew P |
| DOI |
10.1039/c9tc02742d |
| Full Text |
|
| Is Part of |
Journal of materials chemistry C.. London : Royal society of chemistry. 2019, vol. 7, iss. 30, p. 9184-9194.. ISSN 2050-7526. eISSN 2050-7534 |
| Keywords [eng] |
light-emitting-diodes ; external quantum efficiency ; density-functional theory ; molecular design ; emission ; singlet ; tadf ; mechanism ; strategy |
| Abstract [eng] |
We report on the properties of the three positional isomers of (2,7-di-tert-butyl-9,9-dimethylacridin-10(9H)-yl)benzonitrile, which are found to have comparable donor steric environments and donor-acceptor dihedral angles. An unexpected intramolecular dipole interaction imparts a unique molecular geometry to the ortho-linked isomer, while comparison of the meta- and para-isomers uncovers how positional differences in acceptor strengths (a consequence of differences in aromatic pi-system electron density) lead to very different triplet harvesting and emission properties. These positional-isomer effects on TADF follow the well-known aromatic directing rules from organic synthesis, in keeping with their common origin arising from contributions of multiple electronic resonance structures. Understanding these positional effects and methods of dihedral control is critical to the future design of efficient TADF emitters. |
| Published |
London : Royal society of chemistry |
| Type |
Journal article |
| Language |
English |
| Publication date |
2019 |
| CC license |
|
