Side chain structure affects the molecular packing and photovoltaic performance of oligothiophene-based solution-processable small molecules

Abstract

Small molecules with alkyl side chains of different lengths were prepared with 2,2′-bithiophene, terthiophene and thiobarbituric acid as the central core, spacer and end-cap. Uniform, shorter chain lengths gave stronger intermolecular interactions, favoring crystallization.