Theoretical study on electronic structures and spectroscopic properties of indene-C60 monoadduct (ICMA)

ICMA and its derivatives, high performance acceptor of polymer solar cells, have received most attention in experimental and theoretical studies. In this work, we calculated electronic structures and spectroscopic properties of the ICMA by density functional theory (DFT) using B3LYP method. The geometrical structure data show that indene has little influence on C60. In comparison with [6,6]-phenyl C61-butyric acid methyl ester (PCBM), It was proved theoretically that ICMA possesses a better photovoltaic performance and higher LUMO energy level. ICMA and its derivatives could be a promising new acceptor which further improve the power conversion efficiency of the high performance polymer solar cells. The research indicates that the frontier molecular orbital are mainly localized on the C60 sphere, which shows carbon number of cage is an important factor leading to the change of optical and electrical properties. The present study provides theoretical supporting for further application of the ICMA and its derivatives in molecular design and structure-activity relationships research.