1. Universität Göttingen, Institut für Anorganische Chemie, Tammannstraße 4, D-37077Göttingen, Germany
2. Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000Aarhus C, Denmark
3. Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee37831, United States
4. Institut Laue-Langevin (ILL), 71 Avenue des Martyrs, 38042Grenoble, France
5. Laboratoire Léon Brillouin (LLB), CEA CE de Saclay, Gif sur Yvette91191, France
6. Universität Göttingen, International Center for Advanced Studies of Energy Conversion (ICASEC), Tammannstraße 6, D-37077Göttingen, Germany