@misc{DoscheKumkeArieseetal.2003,
  author    = {Dosche, Carsten and Kumke, Michael Uwe and Ariese, F. and Bader, Arjen N. and Gooijer, C. and Dosa, P. I. and Han, S. and Miljanic, O. S. and Vollhardt, K. Peter C. and Puchta, R. and Eikema Hommes, N. J. R. van},
  title     = {Shpol'skii spectroscopy and vibrational analysis of [N]phenylenes},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-13075},
  year      = {2003},
  abstract  = {Vibrationally resolved fluorescence spectra of four angular [N]phenylenes were recorded with laser excited Shpol'skii spectroscopy (LESS) in an n-octane matrix at 10 K. In general, the same vibrational frequencies were observed in the fluorescence excitation and emission spectra, indicating that the geometries of ground and electronically excited state are very similar. Because of intensity borrowing from the S2 state, vibrations of two different symmetries were observed in the fluorescence excitation spectra of angular [3]phenylene and zig-zag[5]phenylene. This finding allowed the location of the S2 state for these compounds. DFT calculations(RB3LYP/6-31G*) of the ground state vibrational frequencies were made. The calculated vibrational modes were in reasonably good agreement with the experimental data. A new very low-frequency vibration of approximately 100 cm-1 was predicted and experimentally confirmed for all [N]phenylenes investigated. This vibration seems to be unique for [N]phenylenes and is attributed to an in-plane movement of the carbon backbone.},
  language  = {de}
}
@misc{BillardAnsoborloAppersonetal.2003,
  author    = {Billard, Isabelle and Ansoborlo, Eric and Apperson, Kathleen and Arpigny, Sylvie and Azenha, M. Emilia and Birch, David and Bros, Pascal and Burrows, Hugh D. and Choppin, Gregory and Kumke, Michael Uwe},
  title     = {Aqueous solutions of Uranium(VI) as studied by time-resolved emission spectroscopy : a Round-Robin Test},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-12318},
  year      = {2003},
  abstract  = {Results of an inter-laboratory round-robin study of the application of time-resolved emission spectroscopy (TRES) to the speciation of uranium(VI) in aqueous media are presented. The round-robin study involved 13 independent laboratories, using various instrumentation and data analysis methods. Samples were prepared based on appropriate speciation diagrams and, in general, were found to be chemically stable for at least six months. Four different types of aqueous uranyl solutions were studied: (1) acidic medium where UO22+aq is the single emitting species, (2) uranyl in the presence of fluoride ions, (3) uranyl in the presence of sulfate ions, and (4) uranyl in aqueous solutions at different pH, promoting the formation of hydrolyzed species. Results between the laboratories are compared in terms of the number of decay components, luminescence lifetimes, and spectral band positions. The successes and limitations of TRES in uranyl analysis and speciation in aqueous solutions are discussed.},
  language  = {en}
}