1. Department
of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
2. Department
of Chemistry and Biochemistry, University of Bern, Freiestrasse
3, CH-3012 Bern, Switzerland
3. Institute
of Chemistry and Biological Chemistry, Zürich University of Applied Sciences, CH-8820 Wädenswil, Switzerland
4. Optical Additives GmbH, Flurweg
9, CH-3073 Gümligen, Switzerland