1. A.V. Shubnikov Institute of Crystallography, Federal Scientific Research Centre “Crystallography and Photonics” of the Russian Academy of Sciences, Leninsky pr. 59, Moscow 119333, Russia
2. Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow 119991, Russia
3. Faculty of Technology of Inorganic Substances and High-Temperature Materials, Mendeleev University of Chemical Technology, Moscow 125047, Russia
4. Ecole Polytechnique Fédérale de Lausanne, Centre Interdisciplinaire de Microscopie Electronique, CH-1015 Lausanne, Switzerland