15 Fakultätsübergreifend / Sonstige Einrichtung

Permanent URI for this collectionhttps://elib.uni-stuttgart.de/handle/11682/16

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Author: search.filters.author.Hausser, Karl H.Subject: search.filters.subject.530

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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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    Spin rotation interaction and anisotropic chemical shift in 13CS2
    (1971) Spiess, Hans Wolfgang; Schweitzer, Dieter; Haeberlen, Ulrich; Hausser, Karl H.
    The 13C nuclear spin-lattice relaxation time T1 was studied in liquid CS2 from -106°C to +35°C at resonance frequencies of 14, 30, and 62 MHz. The relaxation is caused by anisotropic chemical shift and spin-rotation interaction. It is shown that for linear molecules the spin-rotation constant C and the anisotropy of the chemical shift Δσ can be obtained from the relaxation rates without use of adjustable parameters. The analysis yields: C = -13.8 ± 1.4 kHz and Δσ = 438 ± 44 ppm.