1. Universität Kassel, Heinrich-Plett-Str. 40, Kassel 34132, Germany
2. Georg-August-Universität Göttingen, Tammannstr. 6, Göttingen 37077, Germany
3. Max Planck Institut für Biophysikalische Chemie, Am Fassberg 11, Göttingen 37077, Germany
4. Department of Chemistry and Biochemistry, Texas Tech University, Box 41061, Lubbock, TX 79409-1061, USA
5. Institute of Electronic Structure and Lasers, Foundation for Research and Technology - Hellas (FORTH), P. O. Box 1527, Heraklion 71110, Greece
6. Department of Materials Science and Technology, University of Crete, Heraklion 71003, Greece