Influence of backbone fluorination in regioregular poly(3-alkyl-4-fluoro)thiophenes - Fei, Z; Boufflet, P; Wood, S; Wade, J; Moriarty, J; Gann, E; Ratcliff, EL; McNeill, CR; Sirringhaus, H; Kim, JS; Heeney, M (Journal of the American Chemical Society, 2015)