First-principles study on the singlet–triplet energy gap of thermally activated delayed fluorescence molecules. (2nd September 2019)

• Record Type: Journal Article
• Authors: Wei, Yuanfei; Li, Feiyan; Cai, Lei; Shi, Yurong; Zhou, Yong; Lin, Lili
• Is Part Of: Molecular crystals and liquid crystals. Volume 690(2019)
• Page Start: 84
• Page End: 94
• Publication Date: 2019-09-02
• Subjects: Charge transfer -- donors -- energy gap -- thermally activated delayed fluorescence; Molecular crystals -- Periodicals; Liquid crystals -- Periodicals; Liquid crystals; Molecular crystals; Periodicals; 548
• DOI: 10.1080/15421406.2019.1684814
• Languages: English
• ISSNs: 1542-1406

Abstract

Abstract: Recently, thermally activated delayed fluorescence (TADF) molecules have become the research focus and achieved great progress. Since a narrow energy gap between the singlet-excited state (S) and the triplet-excited state (T) is one important condition to realize TADF, it is necessary to make clear the relationship between geometric structures and the S–T energy gap. In this study, 27 molecules composed of three donors and nine acceptors are investigated based on first-principles calculation. Donors have more significant influence than acceptors on their relative orientations. 9, 9-dimethyl-9, 10-dihydroacridine and phenoxazine groups are more effective than carbazole in decreasing the S–T energy gap.