Molecular Design Based on Donor-Weak Donor Scaffold for Blue Thermally-Activated Delayed Fluorescence Designed by Combinatorial DFT Calculations

Youichi Tsuchiya; Keita Tsuji; Ko Inada; Fatima Bencheikh; Yan Geng; H Shaun Kwak; Thomas J L Mustard; Mathew D Halls; Hajime Nakanotani; Chihaya Adachi

doi:10.3389/fchem.2020.00403

Molecular Design Based on Donor-Weak Donor Scaffold for Blue Thermally-Activated Delayed Fluorescence Designed by Combinatorial DFT Calculations

Front Chem. 2020 May 6:8:403. doi: 10.3389/fchem.2020.00403. eCollection 2020.

Authors

Youichi Tsuchiya^{1

2}, Keita Tsuji^{1

3}, Ko Inada^{1

2}, Fatima Bencheikh^{1

2}, Yan Geng¹, H Shaun Kwak⁴, Thomas J L Mustard⁴, Mathew D Halls⁴, Hajime Nakanotani^{1

2

3}, Chihaya Adachi^{1

2

3

5}

Affiliations

¹ Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Fukuoka, Japan.
² Japan Science and Technology Agency (JST), ERATO, Adachi Molecular Exciton Engineering Project, Fukuoka, Japan.
³ Department of Chemistry and Biochemistry, Kyushu University, Fukuoka, Japan.
⁴ Schrödinger Inc, San Diego, CA, United States.
⁵ International Institute for Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University, Fukuoka, Japan.

Abstract

Quantum chemical calculations are necessary to develop advanced emitter materials showing thermally-activated delayed fluorescence (TADF) for organic light-emitting diodes (OLEDs). However, calculation costs become problematic when more accurate functionals were used, therefore it is judicious to use a multimethod approach for efficiency. Here we employed combinatorial chemistry in silico to develop the deep blue TADF materials with a new concept of homo-junction design. The homo-junction materials containing TADF candidates designed by calculation were synthesized and analyzed. We found that these materials showed the emission from charge transfer (CT) state, and the clear delayed emission was provided in solid state. Because the homo-junction TADF materials showed three exponential decayed emission in solid state, we employed novel four-state kinetic analysis.

Keywords: TADF; combinatorial DFT calculation; four-state rate equations; homo-junction design; photo-physics.