1. Department of Materials and
Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden
2. College of Physics/State Key
Laboratory of Superhard Materials, Jilin University, Changchun 130012, People’s Republic of China
3. Max Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569
Stuttgart, Germany
4. Institute
for Condensed Matter
Physics, TU Braunschweig, D-38106 Braunschweig,
Germany
5. Department of Physics, Chung-Ang University, Seoul 156-756, Republic of Korea
6. Department of Chemistry, North Carolina State University, Raleigh, North Carolina
27695-8204, United States
7. Institute of Condensed Matter
Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
8. Dresden High Magnetic Field Laboratory, Forschungszentrum Dresden-Rossendorf, 01314 Dresden,
Germany