1. Helmholtz Institute Ulm (HIU), Helmholtzstrasse 11, D-89081 Ulm, Germany
2. Karlsruhe Institute of Technology (KIT), P.O. Box 3640, D-76021 Karlsruhe, Germany
3. Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, D-89081 Ulm, Germany
4. Central Facility for Electron Microscopy, Group of Electron Microscopy of Materials Science, Ulm University, Albert-Einstein-Allee 11, D-89081 Ulm, Germany