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Author: search.filters.author.Schweitzer, DieterAuthor: search.filters.author.Hausser, Karl H.Institute: search.filters.UBSInstitut.Sonstige EinrichtungStart date: 1979

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Now showing 1 - 10 of 14
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    Electronic spectra and triplet state properties of superphane
    (1986) Schweitzer, Dieter; Hausser, Karl H.; Vogler, Helmut; Staab, Heinz A.; Boekelheide, Virgil
    The emission and the zero-field splitting parameters D and E of the superphane 1 and the [25](1,2,3,4,5)-cyclophane 2 are investigated. The large number of six and five methylene bridges, respectively, leads to a more rigid molecular frame and to a smaller transanular distance as compared to other [2.2]cyclophanes. The experimental results exhibit characteristics features which are due to these unusual properties; they are discussed and compared with semi-empirical Π-electron calculations.
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    Optical detection of magnetic resonance (ODMR) of triple-layered phanes
    (1981) Melzer, Guenter; Schweitzer, Dieter; Hausser, Karl H.; Staab, Heinz A.; Zapf, Udo
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    ODMR of triplet states of organic electron donors
    (1986) Grimm, Hans; Schweitzer, Dieter; Hausser, Karl H.; Keller, Heimo J.
    Energies of the first excited triplet states and triplet zero field splitting parameters /D/ and /E/ of several organic donors - usually used for the preparation of organic metals and superconductors - are reported.
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    Spectroscopic properties of kekulene
    (1981) Schweitzer, Dieter; Hausser, Karl H.; Diederich, Francois; Staab, Heinz A.; Vogler, Helmut
    Kekulene [1,2] is the first example of a new class of aromatic compounds in which the annelation of six membered rings leads to a cyclic system enclosing a cavity with hydrogen atoms.
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    Transanular interaction in [2.2]phanes: models for dimers?
    (1979) Goldacker, Wilfried; Hausser, Karl H.; Schweitzer, Dieter; Staab, Heinz A.
    The emission spectra of pseudo-ortho 3 and pseudo-geminal-4,7,12,15-tetramethoxy[2.2]-paracyclophane 3 were measured in glass matrices at 1.3 K. Furthermore, the zero field splitting parameters D and E and the decay rate constants ki of the excited triplet state were studied by optical detection of magnetic resonance in zero field. The results were compared with the corresponding monomer 1,4-dimethyl-2,5-dimethoxybenzene.
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    Investigation of the excited triplet states of [2.2]- and [3.3]paracyclophane
    (1979) Melzer, Guenter; Schweitzer, Dieter; Hausser, Karl H.; Colpa, Johannes Pieter; Haenel, Matthias
    We have studied the excited triplet states of [2-2]- and [3.3]paracyclophane by emission spectroscopy and by ODMR and have compared the results with the corresponding monomer paraxylene. The most striking result is that both phanes exhibit two sets of zero field splitting parameters indicating the existence of two nearly degenerate low lying excited triplet states. Furthermore, we find in distinction to expection a stronger reduction of the zero field splitting parameters as compared to the monomers for [3.3]paracyclophane than for [2.2]paracyclophane. The causes of these surprising experimental findings are discussed.
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    Optical detection of magnetic resonance (ODMR) of naphthalenophanes
    (1981) Schweitzer, Dieter; Hausser, Karl H.; Blank, Norman E.; Haenel, Matthias
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    ODMR of phanes and charge transfer phanes
    (1979) Schweitzer, Dieter; Goldacker, Wilfried; Hausser, Karl H.; Staab, Heinz A.
    Triplet zero field splitted parameters |D| and |E| and decay rates ki of the triplet sublevels of two stereoisomeric tetramethoxy [2.2] paracyclophanes as well as those of two CT [2.2] paracyclophanes in low concentration in glasses and small neat single ctystals as measured by ODMR in zero fields at 1,3 K are presented.
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    Electron spin echo determination of spin diffusion in the one-dimensional conductor (fluoranthenyl)2+(PF6)x-(SbF6)1-x-(x ≈ 0.5)
    (1983) Sigg, Jakob; Prisner, Thomas; Dinse, Klaus Peter; Brunner, Hermann; Schweitzer, Dieter; Hausser, Karl H.
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    Overhauser effect experiments on the one-dimensional conductor (perylene)2+PF6-·2/3THF
    (1984) Brunner, Hermann; Hausser, Karl H.; Keller, Heimo J.; Schweitzer, Dieter
    We have measured the Overhauser enhancement of the protons and the 19F-nuclei of the one-dimensional conductor (perylene)2+PF6-·2/3THF in its metallic phase at room temperature. The enhancement factor V was found to be VP=+320±20 for the protons and VF=+175±40 for the 19F-nuclei indicating a predominantly scalar interaction with the conduction electrons in both cases.