Title:
On the polarization of the green emission of polyfluorenes

dc.contributor.author Yang, X. H. en_US
dc.contributor.author Neher, D. en_US
dc.contributor.author Spitz, C. en_US
dc.contributor.author Zojer, Egbert en_US
dc.contributor.author Brédas, Jean-Luc en_US
dc.contributor.author Guntner, R. en_US
dc.contributor.author Scherf, U en_US
dc.contributor.corporatename Georgia Institute of Technology. Center for Organic Photonics and Electronics en_US
dc.contributor.corporatename Universität Potsdam. Institut für Physik en_US
dc.contributor.corporatename University of Arizona. Dept. of Chemistry en_US
dc.contributor.corporatename Technische Universität Graz. Institut für Festkörperphysik en_US
dc.contributor.corporatename Bergische Universität Wuppertal. Fachbereich Chemie en_US
dc.contributor.corporatename Bergische Universität Wuppertal. Fachbereich Makromolekulare Chemie en_US
dc.date.accessioned 2013-04-25T20:34:55Z
dc.date.available 2013-04-25T20:34:55Z
dc.date.issued 2003-10
dc.description © 2003 American Institute of Physics. The electronic version of this article is the complete one and can be found at: http://dx.doi.org/10.1063/1.1605374 en_US
dc.description DOI: 10.1063/1.1605374 en_US
dc.description.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. en_US
dc.identifier.citation Yang, X.H. and Neher, D. and Spitz, C. and Zojer, Egbert and Brédas, Jean-Luc and Guntner, R. and Scherf, U., "On the polarization of the green emission of polyfluorenes," Journal of Chemical Physics, 119, 13, 6832-6839 (October 1 2003) en_US
dc.identifier.doi 10.1063/1.1605374
dc.identifier.issn 0021-9606
dc.identifier.uri http://hdl.handle.net/1853/46838
dc.publisher Georgia Institute of Technology en_US
dc.publisher.original American Institute of Physics en_US
dc.subject Polymers en_US
dc.subject Photoluminescence en_US
dc.subject Light polarization en_US
dc.subject Transition moments en_US
dc.subject Charge transfer states en_US
dc.subject Noncrystalline defects en_US
dc.title On the polarization of the green emission of polyfluorenes en_US
dc.type Text
dc.type.genre Article
dspace.entity.type Publication
local.contributor.author Brédas, Jean-Luc
local.contributor.corporatename Center for Organic Photonics and Electronics
relation.isAuthorOfPublication 4d846669-7bb3-480a-8267-9b1cd9ff38d2
relation.isOrgUnitOfPublication 43f8dc5f-0678-4f07-b44a-edbf587c338f
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