1. Department
of Chemistry, Institute for Inorganic Chemistry, University of Cologne, Greinstrasse 6, D-50939 Cologne, Germany
2. Department
of Theoretical Chemistry, Faculty of Chemistry, Jagiellonian University, R. Ingardena 3, 30-060 Cracow, Poland
3. Institut
für Anorganische Chemie, J.-W.-Goethe-Universität, 60323 Frankfurt/Main, Germany