Ultrafast optical probes of excited states in poly(1,4-phenylene vinylene) and poly(2-fluoro-1,4-phenylene vinylene)
We have investigated the photoexcitation dynamics of poly(1,4-phenylene vinylene) (PPV) and poly(2-fluoro-1,4-phenylene vinylene) (PFPV) by using the femtosecond transient absorption spectroscopic technique. It was demonstrated that photoinduced absorption originates from nonemissive indirect polaro...
Gespeichert in:
Veröffentlicht in: | Applied physics letters 1997-08, Vol.71 (5), p.563-565 |
---|---|
Hauptverfasser: | , , , , , , , |
Format: | Artikel |
Sprache: | eng |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | We have investigated the photoexcitation dynamics of poly(1,4-phenylene vinylene) (PPV) and poly(2-fluoro-1,4-phenylene vinylene) (PFPV) by using the femtosecond transient absorption spectroscopic technique. It was demonstrated that photoinduced absorption originates from nonemissive indirect polaron pairs which are more efficiently produced in PFPV than in PPV. The decay processes of polaron pairs are mainly contributed by collisional annihilation and internal conversion by phonon emission in PFPV and PPV, respectively. The differences in photoexcitation dynamics between PPV and PFPV are believed to be caused by the strong electronegativity of substituted fluorine atom. |
---|---|
ISSN: | 0003-6951 1077-3118 |
DOI: | 10.1063/1.120285 |