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Electron affinity and binding energy of excitons in disordered organic semiconductors. III. Multimethod study for films of the blue fluorescent emitter MADN

E. J. de Jong1, N. G. de Rooij1, W. F. M. van Geel1, C. Hauenstein2, H. Tomita1, G. Tirimbò3, M. Berghuis4, S. Gottardi2, B. Baumeier3,5 et al.

R. Coehoorn1,5,*

  • *Contact author: r.coehoorn@tue.nl
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Phys. Rev. B 112, 224204 – Published 4 December, 2025

DOI: https://doi.org/10.1103/kcl9-54vq

Abstract

A method is developed for deducing the electron affinity of disordered organic semiconductors from spectroscopic thin-film studies of the ionization energy and the optical gap energy, combined with field-induced dissociation (FID) device experiments that are analyzed with kinetic Monte Carlo simulations using a methodology that has been presented by de Jong et al., Phys. Rev. B 112, 224202 (2025). The FID experiments are carried out for a set of eight organic semiconductor materials that are often used in organic light-emitting diodes. The analysis is focused on the α and β isomers of the blue fluorescent emitter material 2-methyl-9,10-di-naphthyl-anthracene. For these two materials, the experimental ionization energy, the optical gap energy, the exciton binding energy, and the electron affinity are shown to be consistent with the results of quantum-chemical calculations, presented by G. Tirimbò et al., Phys. Rev. B 112, 224203 (2025). For all fluorescent emitter materials studied, the FID experiments reveal an exciton binding energy of approximately 1.0–1.2 eV, whereas for a thermally activated delayed fluorescence material, a slightly smaller value is obtained.

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Electron affinity and binding energy of excitons in disordered organic semiconductors. I. Simulation-assisted analysis of field-induced exciton dissociation experiments

E. J. de Jong, S. Gottardi, H. van Eersel, and R. Coehoorn
Phys. Rev. B 112, 224202 (2025)

Electron affinity and binding energy of excitons in disordered organic semiconductors. II. First-principles simulations and inverse photoemission studies for MADN

Gianluca Tirimbò, O. Nagaoka, S. Fukushima, Clint van Hoesel, Hiroyuki Yoshida, Reinder Coehoorn, and Björn Baumeier
Phys. Rev. B 112, 224203 (2025)

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Phys. Rev. B 112, 224204– Published 4 December, 2025
  • Received 21 July 2025
  • Accepted 22 October 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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