1. Institute of Physical Chemistry; University of Innsbruck; Innrain 80-82 A-6020 Innsbruck Austria
2. University Service Center for Transmission Electron Microscopy (USTEM); Vienna University of Technology; Wiedner Hauptstraße 8-10 A-1040 Vienna Austria
3. Institute of Mineralogy and Petrography; University of Innsbruck; Innrain 52d A-6020 Innsbruck Austria