Dependence of Charge Separation Efficiency on Film Microstructure in Poly(3-hexylthiophene-2,5-diyl): [6,6]-Phenyl-C61 Butyric Acid Methyl Ester Blend Films - Keivanidis, PE; Clarke, TM; Lilliu, S; Agostinelli, T; Macdonald, JE; Durrant, JR; Bradley, DDC; Nelson, J (JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 2010)