Spectroscopy and Single-Molecule Emission of a Fluorene-Terthiophene Oligomer
Khalil, G. K.
; Adawi, A. M. A.
; Robinson, B.
; Cadby, A. J. C.
; Tsoi, W. C. T.
; Kim, J-S.
;
Charas, A.
;
Morgado, J.
; Lidzey, D. L.
Journal of Physical Chemistry B Vol. 115, Nº 42, pp. 12028 - 12035, October, 2011.
ISSN (print): 1520-6106
ISSN (online): 1520-5207
Scimago Journal Ranking: 1,80 (in 2011)
Digital Object Identifier: 10.1021/jp206368g
Abstract
We study the thiophene-based oligomer poly-
[2,7-(9,9-bis(20-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 00 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.
