Acta Phys. -Chim. Sin. ›› 2014, Vol. 30 ›› Issue (5): 855-865.doi: 10.3866/PKU.WHXB201403113


Charge Transport and Fluorescence Properties of a Series of Red-Emitting Materials Based on Benzothiadiazole and Silafluorene

LI Yan1,2, ZOU Lu-Yi1, REN Ai-Min1   

  1. 1 State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, P. R. China;
    2 Department of Physical Chemistry, School of Chemical and Pharmaceutical Engineering, Jilin Institute of Chemical Technology, Jilin 132022, Jilin Province, P. R. China
  • Received:2014-01-21 Revised:2014-03-10 Published:2014-04-25
  • Contact: REN Ai-Min
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21173099, 20973078, 20673045), National Key Basic Research Program of China (973) (2013CB834801), and Special Funding to Basic Scientific Research Projects for Central Universities, China.


The ground and excited states, charge- transport, and fluorescence properties of a series of polymers based on benzothiadiazole and silafluorene were investigated using density functional theory (DFT). The band gaps, ionization potentials, electron affinities, the lowest excitation energies, and absorption spectra of the polymers were estimated by extrapolating those of the oligomers to infinite chain lengths. The results show that the hole/electron injection/transport abilities and the optical properties of the polymers are significantly affected by the position of the benzothiadiazole group on the silafluorene group and the position of the butyl group on the thiophene group. (SiF2-DHTBT1-m)n and (SiF1-DHTBT1-m)n [hereafter SiF and DHTBT are silafluorene and 4,7-di(2-thienyl)-2,1,3-benzothiadiazole, respectively] show good hole and electron injection performances but (SiF1-DHTBT1-o)n and (SiF1-DHTBT1-p)n exhibit poor carrier injection performances. The predicted emission spectra of the polymers are located in the red visible-light range, except in the case of (SiF1-DHTBT1-o)n.

Key words: Density functional theory, Hole and electron injection, Extrapolation method, Polymer, SiF