Automatic High-Throughput Screening Scheme for Organic Photovoltaics: Estimating the Orbital Energies of Polymers from Oligomers and Evaluating the Photovoltaic Characteristics

A theoretical search for organic photovoltaic materials is immensely helpful for easily identifying candidate materials and ultimately achieving high power conversion efficiencies for solar cells. In this study, an automatic scheme for screening organic photovoltaic (OPV) materials has been developed. This scheme mainly includes three steps, namely, the automatic generation of thiophene-based semiconducting polymers composed of donor and acceptor units, estimation of orbital levels by Hückel-based models, and an evaluation of photovoltaic characteristics. A numerical assessment confirmed that the screening tool could be applied to any calculations with a basis set that includes diffuse functions. An examination of 380 donor–acceptor-type polymers demonstrated that the geometric effects such as effective conjugation length and distortion in the polymers affected the orbital levels and were important to consider in the scheme for screening an ideal OPV material. In addition, the photovoltaic characteristics were evaluated and promising acceptor units for photovoltaic materials were obtained. Thus, the proposed methodology was suitable for high-throughput screening of promising donor/acceptor units.