@phdthesis{Fimmel2015,
  author    = {Fimmel, Benjamin},
  title     = {Perylene Bisimide Foldamers: Synthesis and In-Depth Studies of the Ground- and Excited States Properties},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125173},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {In this thesis the syntheses and detailed investigations on two foldable PBI systems were presented. The reversible, solvent-dependet folding/unfolding-behavior was used to study the ground and excited states properties of folda-dimer and folda-trimer by means of different spectroscopic methods as well as theoretical studies. The switching between charge transfer or excimer formation pathways of photoexcited molecules influenced by the spatial arrangement of chromophores within defined dye systems illustrates the impact of conformational preferences on functional properties.},
  subject      = {Perylenbisdicarboximide <Perylen-3,4:9,10-bis(dicarboximide)>},
  language  = {en}
}
@phdthesis{Klein2015,
  author    = {Klein, Johannes Hubert},
  title     = {Electron Transfer and Spin Chemistry in Iridium-Dipyrrin Dyads and Triads},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-118726},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {The successful synthesis of a family of donor-iridium complex-acceptor triads (T1-T6, pMV1 and mMV1) and their electrochemical and photophysical properties were presented in this work. Triarylamines (TAA) were used as donors and naphthalene diimide (NDI) as acceptor. A bis-cyclometalated phenylpyrazole iridium dipyrrin complex acts as a photosensitiser. In addition, a molecular structure of T1 was obtained by single crystal X-ray diffraction. Transient absorption spectroscopy experiments of these triads resembled that upon excitation a photoinduced electron transfer efficiently generates long-lived, charge-separated (CS) states. Thereby, the electron-transfer mechanism depends on the excitation energy. The presence of singlet and triplet CS states was clarified by magnetic-field dependent transient-absorption spectroscopy in the nanosecond time regime. It was demonstrated that the magnetic field effect of charge-recombination kinetics showed for the first time a transition from the coherent to the incoherent spin-flip regime. The lifetime of the CS states could be drastically prolonged by varying the spacer between the iridium complex and the NDI unit by using a biphenyl instead of a phenylene unit in T4. A mixed-valence (MV) state of two TAA donors linked to an iridium metal centre were generated upon photoexcitation of triad pMV1 and mMV1. The mixed-valence character in these triads was proven by the analysis of an intervalence charge-transfer (IV-CT) band in the (near-infrared) NIR spectral region by femtosecond pump-probe experiments. These findings were supported by TD-DFT calculations. The synthesis of dyads (D1-D4) was performed. Thereby the dipyrrin ligand was substituted with electron withdrawing groups. The electrochemical and photophysical characterisation revealed that in one case (D4) it was possible to generate a CS state upon photoexcitation.},
  subject      = {Elektronentransfer},
  language  = {en}
}