title: Molecular packing effects on the optical spectra and triplet dynamics in oligofluorene films.
abstract: We report on the triplet spectra and dynamics in two types of oligomeric films deposited by two different techniques: thermal evaporation and spin coating. The different molecular arrangement in both films is manifested in a red shift of the absorption, PL, and T1-Tn absorption spectra of the sublimated film relative to the spin-coated one. Triplet recombination dynamics studied with steady-state photoinduced absorption (PA) spectroscopy follow a dispersive bimolecular recombination model away from the trap filling regime. We obtained values for the triplet bimolecular recombination ratio (beta) of 3.4 x 10 (-14) and 1.1 x 10 (-15) cm3 s (-1) for evaporated and spin-coated film, respectively, the difference being attributed to diverse molecular arrangement in both films.
authors: IFN-CNR, Dipartimento di Fisica, ULTRAS-INFM, Politecnico di Milano, Milano 20133, Italy. juan.cabanillas@polimi.it
authors: Juan
authors: J
authors: Cabanillas-Gonzalez
authors: Calogero
authors: C
authors: Sciascia
authors: Guglielmo
authors: G
authors: Lanzani
authors: Stefano
authors: S
authors: Toffanin
authors: Raffaella
authors: R
authors: Capelli
authors: Miguel C
authors: MC
authors: Ramon
authors: Michele
authors: M
authors: Muccini
authors: Johannes
authors: J
authors: Gierschner
authors: Tsyr-Yuan
authors: TY
authors: Hwu
authors: Ken-Tsung
authors: KT
authors: Wong