title: D-A-D-type narrow-bandgap small-molecule photovoltaic donors: pre-synthesis virtual screening using density functional theory.
abstract: A new series of D-A-D-type small-molecule photovoltaic donors are designed and virtually screened before synthesis using time-dependent density functional theory calculations carefully validated against various polymeric and molecular donors. In this series of new design, benzodithiophene is kept as D to achieve the optimum highest-occupied molecular orbital energy level, while thienopyrroledione is initially chosen as A but later replaced by difluorinated benzodiathiazole or its selenide derivative to achieve the optimum band gap. The D-A-D core is end-capped by pyridone units which could not only enhance their self-assembly via hydrogen bonds but also play a role as an acceptor (A') to form an extended A'-D-A-D-A' small-molecule donor.
authors.affiliation: School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea. yhjang@gist.ac.kr shong@gist.ac.kr.
authors.forename: Yeongrok
authors.initials: Y
authors.lastname: Gim
authors.affiliation: School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea. yhjang@gist.ac.kr shong@gist.ac.kr.
authors.forename: Daekyeom
authors.initials: D
authors.lastname: Kim
authors.affiliation: School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea. yhjang@gist.ac.kr shong@gist.ac.kr.
authors.forename: Minkyu
authors.initials: M
authors.lastname: Kyeong
authors.affiliation: School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea. yhjang@gist.ac.kr shong@gist.ac.kr.
authors.forename: Seunghwan
authors.initials: S
authors.lastname: Byun
authors.affiliation: Research Institute for Solar and Sustainable Energies, Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Park
authors.affiliation: Research Institute for Solar and Sustainable Energies, Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
authors.forename: Sooncheol
authors.initials: S
authors.lastname: Kwon
authors.affiliation: Research Institute for Solar and Sustainable Energies, Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
authors.forename: Heejoo
authors.initials: H
authors.lastname: Kim
authors.affiliation: School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea. yhjang@gist.ac.kr shong@gist.ac.kr and Research Institute for Solar and Sustainable Energies, Gwangju Institute of Science and Technology, Gwangju 61005, Korea and Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
authors.forename: Sukwon
authors.initials: S
authors.lastname: Hong
authors.affiliation: GREMAN, UMR 7347, Université François Rabelais, 37200 Tours, France. lansac@univ-tours.fr.
authors.forename: Yves
authors.initials: Y
authors.lastname: Lansac
authors.affiliation: School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea. yhjang@gist.ac.kr shong@gist.ac.kr.
authors.forename: Yun Hee
authors.initials: YH
authors.lastname: Jang