1. Université Paris‐Est, Laboratoire NAVIER (UMR 8205) CNRS ENPC Université Gustave Eiffel F‐77420 Marne‐la‐Vallée France
2. Laboratoire des Solides Irradiés CEA‐CNRS École polytechnique F‐91128 Palaiseau France
3. Centre de Physique Théorique CNRS École polytechnique F‐91128 Palaiseau France
4. Joint Institute for High Temperatures, RAS 13 Building 2 Izhorskaya Street Moscow 125412 Russia
5. Cavendish Laboratory University of Cambridge Cambridge CB3 0HE UK
6. Department of Chemistry University of Cambridge Cambridge CB2 1EW UK
7. Trinity College University of Cambridge Cambridge CB2 1TQ UK
8. St. Catharine's College University of Cambridge Cambridge CB2 1RL UK