1. Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
2. Department of Chemistry, Chemical Engineering Division, Technical University Berlin, 10623 Berlin, Germany
3. ZELMI−Zentraleinrichtung für Elektronenmikroskopie, Technical University Berlin, 10623 Berlin, Germany