| Autor: |
Paras; Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India., Vivek; Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India., Sharma S; Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India., Ramachandran CN; Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India. |
| Jazyk: |
angličtina |
| Zdroj: |
The journal of physical chemistry. A [J Phys Chem A] 2024 Oct 03; Vol. 128 (39), pp. 8428-8435. Date of Electronic Publication: 2024 Sep 19. |
| DOI: |
10.1021/acs.jpca.4c04355 |
| Abstrakt: |
A series of thermally activated delayed fluorescent (TADF) molecules having an imidazopyridine acceptor, a benzene linker, and a 9,9-dimethyl-9,10-dihydroacridine donor are designed and examined using a quantum chemical approach. The above framework spatially separates the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), minimizing their overlap, ultimately resulting in a reduced energy gap between the excited singlet and triplet states (Δ E ST ). The impact of electron-donating substituents (-Me, -Et, - t -Bu, -OMe, and -NMe 2 ) on the donor moiety of the parent molecule 2-(4-(9,9-dimethylacridin-10(9H)-yl)phenyl)imidazo[1,2- a ]pyridine-3,6-dicarbonitrile (Ac-CNImPy) is investigated. The calculated results revealed that for a given substituent, the para-substituted derivatives exhibit relatively less Δ E ST , compared to that of the respective ortho- and meta derivatives. The value of Δ E ST decreased with an increase in the electron-donating capacity of the substituent. Additionally, the Δ E ST of the disubstituted derivatives is found to be less than that for the monosubstituted derivatives. The charge transport studies revealed that molecules with strong electron-donating substituents act as electron transporters. The effect of an external electric field (EEF) on Δ E ST of the parent molecule Ac-CNIMPY and its derivative is also examined and revealed that the Δ E ST can be further reduced by applying an electric field of appropriate strength in a direction perpendicular to the dipole moment of the molecule and in the plane of the acceptor moiety. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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