Chemical Research in Chinese Universities ›› 2017, Vol. 33 ›› Issue (3): 400-405.doi: 10.1007/s40242-017-6506-2

• Articles • Previous Articles     Next Articles

Dynamic Mechanism of Relaxation Paths Occurring in TPA-DCPP: Roles of Solvent and Temperature

ZHONG Qiulin1, CHEN Ying1, WANG Yinghui1,3, CHI Xiaochun1, WANG Yue2, NI Moucui1, ZHANG Hanzhuang1   

  1. 1. Key Laboratory of Physics and Technology for Advanced Batteries, Ministry of Education, College of Physics, Jilin University, Changchun 130012, P. R. China;
    2. State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, P. R. China;
    3. Department of Chemistry, University of California at Irvine, California 92697-2025, USA
  • Received:2016-12-27 Revised:2017-01-24 Online:2017-06-01 Published:2017-04-11
  • Contact: WANG Yinghui,E-mail:yinghui_wang@jlu.edu.cn;ZHANG Hanzhuang,E-mail:zhanghz@jlu.edu.cn E-mail:yinghui_wang@jlu.edu.cn;zhanghz@jlu.edu.cn
  • Supported by:

    Supported by the National Natural Science Foundation of China(Nos.51502109, 21573094, 11274142, 11474131), the Science and Technology Projects in the 13th Five-year Plan in the Education Department of Jilin Province, China(No.2016-402), the National Fund for Fostering Talents of Basic Science, China(No.J1103202) and the Chinese Scholarship Council for Providing Financial Support During Visiting University of California at Irvine, USA.

Abstract:

The relaxation paths for triphenylamine(TPA)-2,3-dicyanopyrazino phenanthrene(DCPP), which has a pull-push structure, were investigated via steady-state, time-resolved spectroscopy involving transient absorption and time-correlated single photon counting. By changing the solvent polarity we found that an intramolecular charge transfer(ICT) state acting as a "bright" state was responsible for the fluorescence character of TPA-DCPP. Meanwhile, a "dark" state gradually appeared and competed with the ICT state. This was likely to be responsible for the polarity-dependent evolution of fluorescence intensity and fluorescence lifetime. The temperature-dependent fluorescence character of the TPA-DCPP in toluene exhibited ICT processes at high temperatures prior to the relaxation path from the initial excited state to the ground state. Our results provide useful insight into the optoelectronic properties of these kinds of molecules.

Key words: Transient absorption spectroscopy, Ultrafast dynamics, Temperature-dependent, Polarity-dependent, In-tramolecular charge transfer state