title: Spectroscopy and single-molecule emission of a fluorene-terthiophene oligomer.
abstract: We study the thiophene-based oligomer poly[2,7-(9,9-bis(2'-ethylhexyl)fluorene)-alt-2,5-terthiophene] (PF3T) in solution and when dispersed at low concentration into a polynorbornene matrix. We find that at high concentration in solution the 0-0 electronic transition observed in fluorescence is suppressed, a result indicative of the formation of weakly coupled H-aggregates. At low concentration in a polymer matrix, emission from both single molecules and molecular aggregates is observed. We find that the fluorescence spectra of most PF3T emitters are composed of a number of relatively narrow emission features, indicating that the emission usually occurs from multiple chromophores. A small number of PF3T molecules are however characterized by single chromophore emission, spectral blinking, and narrowed emission peaks.
authors.affiliation: Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH, United Kingdom.
authors.forename: G E
authors.initials: GE
authors.lastname: Khalil
authors.forename: A M
authors.initials: AM
authors.lastname: Adawi
authors.forename: B
authors.initials: B
authors.lastname: Robinson
authors.forename: A J
authors.initials: AJ
authors.lastname: Cadby
authors.forename: W C
authors.initials: WC
authors.lastname: Tsoi
authors.forename: J-S
authors.initials: JS
authors.lastname: Kim
authors.forename: A
authors.initials: A
authors.lastname: Charas
authors.forename: J
authors.initials: J
authors.lastname: Morgado
authors.forename: D G
authors.initials: DG
authors.lastname: Lidzey
mesh_terms: D005449:Fluorenes / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013876:Thiophenes / Q000737:chemistry*
chemical_list: D005449:Fluorenes; D011108:Polymers; D013876:Thiophenes; C569982:poly(2,7-(9,9-bis(2'-ethylhexyl)fluorene)-alt-2,5-terthiophene); C019101:alpha-terthienyl; C041509:fluorene