1. Departamento de Física, Universidade Federal do Ceará, Campus do Pici, PO Box 6030, 60.455-900 Fortaleza, Ceará, Brazil
2. Centre for Science at Extreme Conditions and School of Chemistry, The University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
3. University of Lille, CNRS, Centrale Lille, ENSCL, University Artois, UMR 8181 - UCCS - Unité de Catalyse et Chimie du Solide, Lille F-59000, France