1. Department
of Physics, University Osnabrück, Barbarastraße 7,
49076 Osnabrück, Germany
2. Laboratory of Bioorganic Chemistry
and Chemical Biology, Center for Nanotechnology, Heisenbergstraße 11, 48149 Münster, Germany
3. Laboratory of Organic and Bioorganic
Chemistry, Department of Chemistry, University Osnabrück, Barbarastraße 7, 49076 Osnabrück, Germany