1. Institut für Anorganische Chemie, Karlsruhe Institute of Technology, University of Karlsruhe, Engesserstrasse 15, D-76131 Karlsruhe, Germany
2. Institut Néel CNRS, BP 166, 25 avenue des Martyrs, F-38042 Grenoble, France
3. CNRS, UPR 8641, Centre de Recherche Paul Pascal Equipe “Matériaux Moléculaires Magnétiques”, 115 avenue du Dr. Albert Schweitzer, F-33600 Pessac, France
4. Université de Bordeaux, UPR 8641, F-33600, Pessac, France
5. Institut für Synchrotronstrahlung, Karlsruhe Institute of Technology, Forschungszentrum Karlsruhe, D-76344 Eggenstein-Leopoldshafen, Germany
6. Department of Physics, University of Liège, B-4000 Sart-Tilman, Belgium
7. Department of Chemistry, Missouri University of Science and Technology, University of Missouri, Rolla, Missouri 65409-0010