Effects of Carbon-sp3 Bridging on the Electronic Properties of Oligothiophenes

The electronic properties of rigidified, carbon sp3-bridged bithiophenes and terthiophenes have been investigated using density functional theory calculations, sp3 Bridging has no effect on the bandgap other than that associated to the planarization of the system. Rigidification significantly improves the ability of oligothiophenes as electron donors but diminishes their electron accepting capacity. Grafting of substituents at the sp3 bridging carbon slightly modifies the electronic properties.