03 Fakultät Chemie

Permanent URI for this collectionhttps://elib.uni-stuttgart.de/handle/11682/4

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Institute: search.filters.UBSInstitut.3. Physikalisches InstitutAuthor: search.filters.author.Effenberger, Franz

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Now showing 1 - 4 of 4
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    The mechanism of intramolecular energy transfer in terminally substituted polyene molecules
    (1993) Holl, Norbert; Port, Helmut; Wolf, Hans Christoph; Strobel, Hartmut; Effenberger, Franz
    Absorption, fluorescence and excitation spectra of different terminally substituted polyenes have been recorded in the UV-Vis region. The observed intramolecular unidirectional energy transfer from a donor substituent to an acceptor at the other end of the chain is influenced but not inhibited by incorporation of a spacer into the polyene chain. In molecules without a spacer, internal conversion within the supermolecule can explain the observed transfer of energy. In molecules with a spacer interrupting the polyene chain the observed intramolecular energy transfer can be explained in terms of Förster transfer.
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    Localized states in anthrylpolyenes : influence of geometry
    (1990) Heine, Barbara; Sigmund, Ernst; Maier, Stefan; Port, Helmut; Wolf, Hans Christoph; Effenberger, Franz; Schlosser, Hubert
    Combining group theoretical arguments and (extended) Hückel calculations, it is shown that terminally anthryl-substituted polyenes exhibit states almost completely localized at the substituents. These localized states are related to characteristic optical transitions in anthracene which also are observed in anthrylpolyenes independent of the length of the polyene chain.
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    Synthesen und optische Eigenschaften endständig substituierter konjugierter Polyene
    (1988) Effenberger, Franz; Schlosser, Hubert; Bäuerle, Peter; Maier, Stefan; Port, Helmut; Wolf, Hans Christoph
    Wir berichten hier über die Synthese konjugierter Polyene unterschiedlicher Länge, die endständig Substituenten tragen, deren spektroskopische Eigenschaften sich von denen der Polyenkette unterscheiden. Anhand von Absorptions-, Emissions- und Anregungsspektren werden die gezielte optische Anregung dieser Modellverbindungen und die Möglichkeiten eines intramolekularen Energietransports diskutiert.
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    Lowest excited singlet states of α-9-anthrylpolyenes
    (1993) Holl, Norbert; Emele, Peter; Port, Helmut; Wolf, Hans Christoph; Strobel, Hartmut; Kesmarszky, Thomas; Effenberger, Franz
    Properties of the electronically excited states of α-9-anthrylpolyenes are studied in n-hexane solutions by using optical absorption, emission and fluorescence excitation spectroscopy. The absorption spectra reveal a complex structure with contributions of both anthracene and polyene type bands but also of bands with mixed anthracence/polyene character. Small amounts of remaining impurities are chemically not separable but can be detected via fluorescence measurements. By computer-aided decomposition of spectra measured under variable selective excitation the actual, clearly chain-length dependent, fluorescences could be obtained.