Journal of Fluorescence

, Volume 17, Issue 6, pp 749–757 | Cite as

Single Molecule Spectroscopy of Poly 3-octyl-thiophene (P3OT)

Original Paper


We report on the spectroscopy of isolated chains of P3OT, in a highly dilute solution in the inert polymer host poly(methyl–methacrylate) (PMMA). This environment permits a detailed analysis of emission transitions in the 1.9–2.2 eV range by suppressing the formation of the lowest emitting-energy aggregated form of P3OT. Herein it is observed that the 1.9–2.2 eV band is in fact split into low (red) and high (blue) energy forms in a highly analogous situation to that found for the conjugated polymer MEH-PPV. Another focus of this work is an investigation of the interaction of singlet and triplet excitons in P3OT. The results indicate that, like in MEH-PPV, triplet excitons are highly efficient fluorescence quenchers for P3OT, strongly quenching the fluorescence of P3OT under even relatively low excitation intensities.


Single molecule spectroscopy Poly 3-alkyl-thiophene (P3AT) Poly-3-octyl-thiophene (P3OT) Bimodal emission Singlet–triplet interaction 



We gratefully acknowledge the Basic Energy Sciences Program of the Department of Energy and the Robert A. Welch Foundation for support of this research. We thank Brent C. Norris for making the nanoparticle samples that were studied in this paper.


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  1. 1.Department of Chemistry and Biochemistry and the Center for Nano- and Molecular Science and TechnologyUniversity of TexasAustinUSA
  2. 2.AustinUSA

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