1. L.F. Vereshchagin Institute for High Pressure Physics, The Russian Academy of Sciences, Troitsk, Russia
2. GREMAN, UMR CNRS-7347, INSA CVL, University of Tours, Tours, France
3. School of Mathematics and Physics, The University of Queensland, Saint Lucia, Australia
4. Department of Materials Science and Nanoengineering, Rice University, Houston, TX, USA