Theoretical Characterizations on Charge Transfer Excitations in Solution by Time-Dependent Density Functional Theory A Case Study

Tzu Ting Huang, Tsao Pei Chou, Elise Yu-Tzu Li

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

It is a well-known issue that the application of time-dependent density functional theory (TD-DFT) on charge transfer excitations often leads to a severe underestimation if the non-local exchange energy is not properly included. Here we perform a careful first-principles investigation on a specific molecular system that is known to exhibit thermally activated delayed fluorescence (TADF) phenomenon, using three different functions, B3LYP, CAM-B3LYP, and M06-2X. We find that even in functionals with more adequately described or fitted long-range exchange part, the triplet excitation energy levels may still show a large variation, indicating that the performance of a specific functional cannot solely be based on the comparison with the absorption or emission spectra. An inclusion of the solvent effect adds to further complexity. Since the efficiency of TADF is directly related to the energy gaps between low-lying singlet and triplet excited states, the proposed underlying mechanism to illustrate photophysical processes would be intimately associated to the chosen functional and the treatment of the polar medium.

Original languageEnglish
Pages (from-to)465-471
Number of pages7
JournalJournal of the Chinese Chemical Society
Volume63
Issue number6
DOIs
Publication statusPublished - 2016 Jun 1

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Density functional theory
Charge transfer
Fluorescence
Excitation energy
Computer aided manufacturing
Excited states
Electron energy levels
Energy gap

Keywords

  • Charge-transfer excitations
  • Solvation
  • TDDFT
  • Thermally activated delayed fluorescence

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Theoretical Characterizations on Charge Transfer Excitations in Solution by Time-Dependent Density Functional Theory A Case Study. / Huang, Tzu Ting; Chou, Tsao Pei; Li, Elise Yu-Tzu.

In: Journal of the Chinese Chemical Society, Vol. 63, No. 6, 01.06.2016, p. 465-471.

Research output: Contribution to journalArticle

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