Study on Photoelectric Properties of Donor DCCnT with Different Substituents

• 1、Faculty of Materials and Energy, Southwest University, Chongqing, 400715

Abstract：The structure of the accepting small molecule has the characteristics of easy adjustment, small molecular weight and easy synthesis, so that this kind of molecule can be easily transformed and designed through the structure, and can exhibit properties different from the mother. These advantages make the design and transformation of small molecules a path to find new types of solar cell materials. In addition to changing the structure of solar cells, another method is expected to improve the photoelectric conversion efficiency of solar cells. In this paper, we study the novel donor and acceptor molecules Study on Photoelectric Properties of Donor DCCnT with Different Substituents(DCCnT) as donor materials, HOMO, LUMO and GAP values, UV and visible spectrum and exciton binding energy under different electron donating groups, and try to predict the most through the results. The potential to accept the integrated small molecule material as a solar cell donor material. We used B3LYP, CAM-B3LYP and OmegaB97XD to predict the small molecules HOMO, LUMO and GAP, and compared with the experimental values, we found that the functional CAM-B3LYP can better present the experimental values. This functional CAM-B3LYP will then be used to calculate the exciton binding energy. Theoretical calculations show that the small molecule obtained by the substitution of a strong electron donating group exhibits a lower GAP value and a lower exciton binding energy. And the calculated UV and visible spectra of DCCnT molecules have a blue shift trend compared with experimental data

Keywords： Physical Chemistry；time-dependent density functional； donor-acceptor molecule；electron-donating group；absorption spectrum； exciton binding energy