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Updated: Jun 17, 2026
09:32
Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Polymer glass transitions switch electron transfer in individual molecules
Joanna R Siekierzycka1, Catharina Hippius, Frank Würthner
1Van't Hoff Institute for Molecular Sciences, Universiteit van Amsterdam, Nieuwe Achtergracht 129, 1018 WS Amsterdam, The Netherlands.
Journal of the American Chemical Society
|January 7, 2010
Summary
Photoinduced electron transfer in perylene-calixarene compounds is quenched above the glass transition temperature (Tg) in polymers. Fluorescence is fully recovered below Tg, enabling reversible on/off switching at the single-molecule level.
Area of Science:
- Polymer Science
- Photochemistry
- Materials Science
Background:
- Fluorescence quenching is a key phenomenon in photochemistry.
- Controlling molecular behavior within polymer matrices is crucial for developing advanced materials.
Purpose of the Study:
- To investigate the photoinduced electron transfer quenching of perylene-calixarene compounds in polymer matrices.
- To explore the temperature-dependent fluorescence switching behavior of these systems.
Main Methods:
- Utilizing perylene-calixarene compounds as fluorescent probes.
- Employing polymer matrices such as poly(methyl acrylate) and poly(vinyl acetate).
- Monitoring fluorescence properties in relation to polymer glass transition temperatures (Tg).
Main Results:
- Complete photoinduced electron transfer quenching observed above the polymer Tg.
- Full fluorescence recovery upon cooling below the Tg.
- Demonstration of reversible on/off fluorescence switching at the single-molecule level.
Conclusions:
- The study demonstrates a novel mechanism for reversible fluorescence switching in polymers.
- This phenomenon is directly linked to the polymer's thermal properties (Tg).
- Potential applications in molecular switches and sensors.
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