1. Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, von-Liebig-Straße 20, Rheinbach D-53359, Germany
2. Department of Chemistry and Biotechnology, FH Aachen University of Applied Sciences, Heinrich-Mußmann-Straße 1, Jülich 52428, Germany
3. Institute of Chemistry, Saratov State University, Astrakhanskaya Street 83, 410012 Saratov, Russia
4. Spectral Service AG, Emil-Hoffmann-Straße 33, D-50996 Köln, Germany
5. Department of Chemistry, Technical University of Darmstadt, Alarich-Weiss-Straße 4, Darmstadt D-64287, Germany