LAUSR

Abstract Here, we have reported a series of exciting conducting organic heterocyclic oligomers possessing the cyclopentadithiophene-4-thione-triazole-cyclopentadithiophene-4-thione (DT-Tr-DT) as basic unit based on the donor-acceptor (D-A) approach. The basic unit is substituted with different electron-withdrawing and donating groups to tune its structural and electronic properties. Density functional theory (DFT) and time-dependent DFT methodologies were utilized to investigate the ground and excited state calculation. Here, our main focus is on the HOMO-LUMO gaps, electronic transition, charge transfer rate and the reorganization energies ( λ ). Our study reveals that the designed oligomers under investigation exhibit excellent charge transfer rates. Furthermore, it has also been reported that oligomers substituted with the electron-donating groups exhibit lower Δ H - L values compared to the electron-withdrawing groups. Therefore, oligomers substituted with electron-donating moieties will become potential candidates for fabrication of organic light emitting diodes (OLEDs), organic field effect transistors (OFETs), photovoltaic cells and solar cells.