1. High Field Magnet Laboratory (HFML-EMFL) and Institute for Molecules and Materials, Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
2. Physikalisches Institut, Universität zu Köln, Zülpicher Str., 77, 50937 Köln, Germany
3. Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
4. Hochfeld-Magnetlabor Dresden (HLD-EMFL), Helmholtz-Zentrum Dresden-Rossendorf, D-01314 Dresden, Germany