A series of new donor–acceptor π-conjugated copolymers incorporating 5, 10-dihydroindolo [3, 2-b] indole (DINI) as an electron donating unit have been designed, synthesized, and explored in bulk heterojunction solar cells with diketopyrrolopyrrole and thienopyrroledione as the electron accepting units. A significant effect of the size and shape of the pendant alkyl substituents attached to the DINI unit on the optical and electronic properties of the ...
[Murray, Michael M.; Kaszynski, Piotr; Kaisaki, David A.; Chang, Wonghil; Dougherty, Dennis A. Journal of the American Chemical Society, 1994 , vol. 116, # 18 p. 8152 - 8161]