• Login
    View Item 
    •   SMARTech Home
    • Center for Organic Photonics and Electronics (COPE)
    • COPE Publications
    • View Item
    •   SMARTech Home
    • Center for Organic Photonics and Electronics (COPE)
    • COPE Publications
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    On the polarization of the green emission of polyfluorenes

    Thumbnail
    View/Open
    COPE_094.pdf (529.2Kb)
    Date
    2003-10
    Author
    Yang, X. H.
    Neher, D.
    Spitz, C.
    Zojer, Egbert
    Brédas, Jean-Luc
    Guntner, R.
    Scherf, U
    Metadata
    Show full item record
    Abstract
    An experimental and theoretical study of the anisotropic optical properties of polyfluorenes (PFs) bearing ketonic defects is presented. Polarized emission experiments performed on photooxidized aligned PF layers indicate that the transition dipole of the ‘‘green’’ CT π-π * transition of the keto-defect is oriented parallel to the chain direction. It is further observed that the polarization ratio of the green emission is slightly smaller than that of the blue emission component originating from undisturbed chains. Quantum mechanical calculations have been performed to support these observations. It is shown that the transition dipole moment of the CT π-π * transition of the defect is slightly misaligned with respect to the π-π* transition of the undisturbed PF chain, and that the angle between both depends on the chain conformation. For the most probably 5/2 helical conformation, this angle is, however, smaller than 5°. Further, polarized PL spectroscopy with polarized excitation has been performed to determine the extent of energy migration prior to emission from the keto-defect. For excitation at 380 nm, the polarization ratio of the green emission is essentially independent of the excitation polarization, indicating almost complete depolarization of the excitation before it is captured at a defect site. In contrast to this, energy migration after direct excitation of the keto-defect is inefficient or even absent.
    URI
    http://hdl.handle.net/1853/46838
    Collections
    • COPE Publications [376]

    Browse

    All of SMARTechCommunities & CollectionsDatesAuthorsTitlesSubjectsTypesThis CollectionDatesAuthorsTitlesSubjectsTypes

    My SMARTech

    Login

    Statistics

    View Usage StatisticsView Google Analytics Statistics
    • About
    • Terms of Use
    • Contact Us
    • Emergency Information
    • Legal & Privacy Information
    • Accessibility
    • Accountability
    • Accreditation
    • Employment
    • Login
    Georgia Tech

    © Georgia Institute of Technology

    • About
    • Terms of Use
    • Contact Us
    • Emergency Information
    • Legal & Privacy Information
    • Accessibility
    • Accountability
    • Accreditation
    • Employment
    • Login
    Georgia Tech

    © Georgia Institute of Technology