Abstract
Single molecule confocal fluorescence microscopy was used to perform photoluminescence spectroscopy on single, isolated molecules of derivatives of the conjugated polymer poly(p-phenylenevinylene). We show that the fluorescence from single chains of these electroluminescent polymers depends strongly on chain conformation. Extended chains show emission from multiple segments, while tightly-folded chains emit only from few distinct sites. The tight coil in folded chains enables the polymer to funnel excitons to highly aggregated low energy regions via three-dimensional Foerster-type energy transfer. This strong intrachain coupling causes these polymers to mimic the photophysical behavior of single chromophores and leads to localized emission and fluorescence intermittency. Polymer molecules that have specifically designed steric hindrance for backbone contacts show higher resistance to solvent-induced interaction between its segments. Only the introduction of non-solvents to such systems forces the polymer to stack its backbone and form aggregates. The luminescence of these buckled polymer chains shows distinctly red-shifted emission presumably due to excimer-formation. These results have significant implications for photophysics and photochemistry of conjugated polymers and their application in thin film electronic devices.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 43-51 |
| Number of pages | 9 |
| Journal | Journal of Photochemistry and Photobiology A: Chemistry |
| Volume | 144 |
| Issue number | 1 |
| State | Published - Oct 31 2001 |
| Externally published | Yes |
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Keywords
- Aggregates
- Conjugated polymers
- Photoluminescence spectroscopy
- Single molecules
ASJC Scopus subject areas
- Bioengineering
- Physical and Theoretical Chemistry
Cite this
Solvent-related conformational changes and aggregation of conjugated polymers studied by single molecule fluorescence spectroscopy. / Huser, Thomas R; Yan, Ming.
In: Journal of Photochemistry and Photobiology A: Chemistry, Vol. 144, No. 1, 31.10.2001, p. 43-51.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Solvent-related conformational changes and aggregation of conjugated polymers studied by single molecule fluorescence spectroscopy
AU - Huser, Thomas R
AU - Yan, Ming
PY - 2001/10/31
Y1 - 2001/10/31
N2 - Single molecule confocal fluorescence microscopy was used to perform photoluminescence spectroscopy on single, isolated molecules of derivatives of the conjugated polymer poly(p-phenylenevinylene). We show that the fluorescence from single chains of these electroluminescent polymers depends strongly on chain conformation. Extended chains show emission from multiple segments, while tightly-folded chains emit only from few distinct sites. The tight coil in folded chains enables the polymer to funnel excitons to highly aggregated low energy regions via three-dimensional Foerster-type energy transfer. This strong intrachain coupling causes these polymers to mimic the photophysical behavior of single chromophores and leads to localized emission and fluorescence intermittency. Polymer molecules that have specifically designed steric hindrance for backbone contacts show higher resistance to solvent-induced interaction between its segments. Only the introduction of non-solvents to such systems forces the polymer to stack its backbone and form aggregates. The luminescence of these buckled polymer chains shows distinctly red-shifted emission presumably due to excimer-formation. These results have significant implications for photophysics and photochemistry of conjugated polymers and their application in thin film electronic devices.
AB - Single molecule confocal fluorescence microscopy was used to perform photoluminescence spectroscopy on single, isolated molecules of derivatives of the conjugated polymer poly(p-phenylenevinylene). We show that the fluorescence from single chains of these electroluminescent polymers depends strongly on chain conformation. Extended chains show emission from multiple segments, while tightly-folded chains emit only from few distinct sites. The tight coil in folded chains enables the polymer to funnel excitons to highly aggregated low energy regions via three-dimensional Foerster-type energy transfer. This strong intrachain coupling causes these polymers to mimic the photophysical behavior of single chromophores and leads to localized emission and fluorescence intermittency. Polymer molecules that have specifically designed steric hindrance for backbone contacts show higher resistance to solvent-induced interaction between its segments. Only the introduction of non-solvents to such systems forces the polymer to stack its backbone and form aggregates. The luminescence of these buckled polymer chains shows distinctly red-shifted emission presumably due to excimer-formation. These results have significant implications for photophysics and photochemistry of conjugated polymers and their application in thin film electronic devices.
KW - Aggregates
KW - Conjugated polymers
KW - Photoluminescence spectroscopy
KW - Single molecules
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UR - http://www.scopus.com/inward/citedby.url?scp=0002669821&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0002669821
VL - 144
SP - 43
EP - 51
JO - Journal of Photochemistry and Photobiology A: Chemistry
JF - Journal of Photochemistry and Photobiology A: Chemistry
SN - 1010-6030
IS - 1
ER -