1. University of Vienna
2. Institute of Inorganic Chemistry
3. A-1090 Vienna
4. Austria
5. Department of Medical Microbiology and Immunobiology
6. University of Szeged
7. H-6720 Szeged
8. Hungary
9. Department of Inorganic and Analytical Chemistry
10. Laboratoire National des Champs Magnetiques Intenses-CNRS
11. 38042 Grenoble Cedex 9
12. France