Importance of unpaired electrons in organic electronics
Jonathan D. Yuen, Mingfeng Wang, Jian Fan, Dennis Sheberla, Moureen Kemei, Natalie Banerji, Mariateresa Scarongella, Sebastian Valouch, Toan Pho, Rajeev Kumar, Eneida C. Chesnut, Michael Bendikov and Fred Wudl
Article first published online: 11 AUG 2014 | DOI: 10.1002/pola.27321
PBBTPD, a low bandgap, ambipolar conjugated donor-acceptor polymer based on benzobisthiadiazole (BBT), is shown to possess an open-shell singlet ground state as well as a thermally accessible triplet state. Theoretical predictions have suggested that such behavior is due to the biradicaloid character of BBT. This biradicaloid structure is in each BBT moiety and therefore PBBTPD is in fact a polyradicaloid. These observations will aid in development of better n-type polymeric acceptors for organic semiconductor applications.