Skip to content
DraconiticResearch
Search Sources API
203,234 studies31 sourcesUpdated 1 h ago
Peer-reviewedCC BY 3.0RSC Advances

Theoretical insights into the thermally activated delayed fluorescence of pyridazine derivatives: balancing twist and charge-transfer character

  • Yan Liu1,2,3
  • Shuhua Ma1
  • Yuanyuan Yang1
  • Chunhua Qu1
  • Junyan Zhou1,3
  • Yushan Wang1,3
  • Yibin Yang4
  • Weiguo Cao1
4 affiliations
  1. 1School of Chinese Materia Medica, Chongqing College of Traditional Chinese Medicine Chongqing 402760 China
  2. 2Chongqing Traditional Chinese Medicine Hospital Chongqing 400021 China
  3. 3Modern Chinese Medicine Industry College, Chongqing College of Traditional Chinese Medicine Chongqing 402760 China
  4. 4Chemical Pollution Control Chongqing Applied Technology Extension Center of Higher Vocational Colleges, Chongqing Industry Polytechnic University Chongqing 401120 China
Read full textPDFDOICite

Abstract

In this work, a systematic theoretical study of 4,5,6-triphenylpyridazine-3-carbonitrile-based (TPPz-based) donor–acceptor molecules reveals that donor steric bulk critically controls molecular planarity and excited-state properties. The moderately bulky electron-donating 4-(bis(4-(tert-butyl)phenyl)amino)phenyl (BPA) moiety induces the largest overall molecular distortion and yields a nearly pure CT S1 state together with an HLCT T1 state. In contrast, the rigid pyrenyl donor in 4,6-diphenyl-5-(4-(pyren-1-yl)phenyl)pyridazine-3-carbonitrile (Pyr-TPPz) gives a CT S1 state but a locally excited T1 state. 5-(4-(bis(4-(tert-butyl)phenyl)amino)phenyl)-4,6-diphenylpyridazine-3-carbonitrile (BPA-TPPz) exhibits the lowest reorganization energy (2513 cm−1), efficiently suppressing nonradiative decay, and shows the highest krisc among the series. TPPz and Pyd-TPPz exhibit moderate RISC, whereas Pyr-TPPz shows a very low k_RISC within the S1–T1 two-state approximation because of its large S1–T1 gap, despite its LE T1 character. These results establish that optimal thermally activated delayed fluorescence performance requires a delicate balance between a twisted architecture for exciton management, suitable donor–acceptor electronic structures to modulate charge-transfer/locally excited (CT/LE) hybridization, and flexible donors to minimize reorganization energy. These findings provide clear structure–property guidelines for the design of efficient thermally activated delayed fluorescence (TADF) materials.

Related

  1. Thermally Activated Delayed Fluorescence: An Extended Study of Peripherally Substituted DMAC‐TRZ Analogues
    Andrea Landi, Ottavia Racchi, D. K. Andrea Phan Huu +5
    Chemistry (Weinheim an Der Bergstrasse, Germany)Peer-reviewedCC BY 4.0Full textOrganic chemistryPMC
  2. Thermally activated delayed fluorescence in neutral and cationic stages of aza-nanographene decorated with 6.6.6 defects.
    Rohith Valavil Suku, Illia E Serdiuk, Krzysztof Dzieszkowski +5
    Chemical sciencePeer-reviewedCC BYFull textOrganic chemistryEurope PMC
  3. A Terminal Carbazole Fused Ladder‐Type B,N‐Doped Multiresonant Thermally Activated Delayed Fluorescence Emitter: A Strategy for Deep‐Blue Emission
    Abhishek Kumar Gupta, Shantaram S. Kothavale, Aidan P. McKay +4
    ChemistryEuropePeer-reviewedCC BYFull textOrganic chemistryDOAJ
  4. Efficient Long-Wavelength Through-Space Charge Transfer Thermally Activated Delayed Fluorescence in Conformationally Adaptive Emitters without Conformational Locking
    Nae Aota, Jaijanarthanan Lingagouder, Nuno Gandum +8
    ChemRxivPreprintCC BYFull textGeneral chemistryChemRxiv
  5. Phase-Dependent Thermally Activated Self-Discharge of β-NiOOH and γ-NiOOH Electrodes
    Elena Praznikov, Avigail Varveri Landman, Avner Rothschild
    ChemRxivPreprintCC BYFull textElectrochemistry & energyChemRxiv

Cite

BibTeXRIS
BibTeX
@article{liu2026theoretical,
  title = {{Theoretical insights into the thermally activated delayed fluorescence of pyridazine derivatives: balancing twist and charge-transfer character}},
  author = {Yan Liu and Shuhua Ma and Yuanyuan Yang and Chunhua Qu and Junyan Zhou and Yushan Wang and Yibin Yang and Weiguo Cao},
  journal = {RSC Advances},
  year = {2026},
  month = oct,
  doi = {10.1039/d6ra07215a},
  url = {https://doi.org/10.1039/d6ra07215a},
  note = {CC BY 3.0},
}
RIS
TY  - JOUR
TI  - Theoretical insights into the thermally activated delayed fluorescence of pyridazine derivatives: balancing twist and charge-transfer character
AU  - Yan Liu
AU  - Shuhua Ma
AU  - Yuanyuan Yang
AU  - Chunhua Qu
AU  - Junyan Zhou
AU  - Yushan Wang
AU  - Yibin Yang
AU  - Weiguo Cao
PY  - 2026
DA  - 2026/10/08
JO  - RSC Advances
DO  - 10.1039/d6ra07215a
UR  - https://doi.org/10.1039/d6ra07215a
AB  - In this work, a systematic theoretical study of 4,5,6-triphenylpyridazine-3-carbonitrile-based (TPPz-based) donor–acceptor molecules reveals that donor steric bulk critically controls molecular planarity and excited-state properties. The moderately bulky electron-donating 4-(bis(4-(tert-butyl)phenyl)amino)phenyl (BPA) moiety induces the largest overall molecular distortion and yields a nearly pure CT S1 state together with an HLCT T1 state. In contrast, the rigid pyrenyl donor in 4,6-diphenyl-5-(4-(pyren-1-yl)phenyl)pyridazine-3-carbonitrile (Pyr-TPPz) gives a CT S1 state but a locally excited T1 state. 5-(4-(bis(4-(tert-butyl)phenyl)amino)phenyl)-4,6-diphenylpyridazine-3-carbonitrile (BPA-TPPz) exhibits the lowest reorganization energy (2513 cm−1), efficiently suppressing nonradiative decay, and shows the highest krisc among the series. TPPz and Pyd-TPPz exhibit moderate RISC, whereas Pyr-TPPz shows a very low k_RISC within the S1–T1 two-state approximation because of its large S1–T1 gap, despite its LE T1 character. These results establish that optimal thermally activated delayed fluorescence performance requires a delicate balance between a twisted architecture for exciton management, suitable donor–acceptor electronic structures to modulate charge-transfer/locally excited (CT/LE) hybridization, and flexible donors to minimize reorganization energy. These findings provide clear structure–property guidelines for the design of efficient thermally activated delayed fluorescence (TADF) materials.
SN  - 2046-2069
ER  -