Theor etical investigation of phenyl group effect as an end-substitution o n electronic propert ies of oligothiophenes

Oligothi ophenes have received great attenti on over the past few years for their potential use in a variety of devi ces, includi ng nonlinear optics, Schottky diod es, organic light-emittin g diodes ( OLEDs), an d thin-film field-effect transistors (F ETs) [۱]. One approach to develop a higher p erformance of oligothiophenes is th e introduction of substituent at spe cific positio n of monomer ring. T he other ap proach is to cap both ends of the thiophene chain by t he substitut on groups. The capped -oligothiop henes have a well-defined molecular size and a high chemical stability. Recently, it has f ound that phenyl-cappe d oligothiophenes (Pn T,where n is number of thiophene ring) have novel light -emitting properties [۲]. In this work we investigated the lectronic properties of phenyl-capped oligothio phene including HOM O- LUMO gap, first e xcitation energy, charge distributio n, ionizatio n potential and electro n affinity.

کلیدواژه ها:

DFT ، E nd-substitution ، Electron ic properties ، Oligothiophenes