Thermally Activated Delayed Fluorescence: Polarity, Rigidity, and Disorder in Condensed Phases

Phan Huu, D.K. Andrea; Saseendran, Sangeeth; Dhali, Rama; Gomes Franca, Larissa; Stavrou, Kleitos; Monkman, Andrew; Painelli, Anna

Abstract

We present a detailed and comprehensive picture of the photophysics of thermally activated delayed fluorescence (TADF). The approach relies on a few-state model, parametrized ab initio on a prototypical TADF dye, that explicitly accounts for the nonadiabatic coupling between electrons and vibrational and conformational motion, crucial to properly address (reverse) intersystem crossing rates. The Onsager model is exploited to account for the medium polarity and polarizability, with careful consideration of the different time scales of relevant degrees of freedom. TADF photophysics is then quantitatively addressed in a coherent and exhaustive approach that accurately reproduces the complex temporal evolution of emission spectra in liquid solvents as well as in solid organic matrices. The different rigidity of the two environments is responsible for the appearance in matrices of important inhomogeneous broadening phenomena that are ascribed to the intertwined contribution from (quasi)static conformational and dielectric disorder.

Citation

Phan Huu, D. A., Saseendran, S., Dhali, R., Gomes Franca, L., Stavrou, K., Monkman, A., & Painelli, A. (2022). Thermally Activated Delayed Fluorescence: Polarity, Rigidity, and Disorder in Condensed Phases. Journal of the American Chemical Society, 144(33), 15211 - 15222. https://doi.org/10.1021/jacs.2c05537

• Journal Article Type: Article
• Online Publication Date: Aug 9, 2022
• Publication Date: 2022
• Deposit Date: Sep 15, 2022
• Publicly Available Date: Sep 15, 2022
• Journal: Journal of the American Chemical Society
• Print ISSN: 0002-7863
• Electronic ISSN: 1520-5126
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 144
• Issue: 33
• Pages: 15211 - 15222
• DOI: https://doi.org/10.1021/jacs.2c05537