1. Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543 Singapore
2. Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften, Philipps Universität Marburg, Hans‐Meerwein‐Straße, 35043 Marburg, Germany
3. Current address: Division of Chemical and Forensic Sciences, University of Bradford, West Yorkshire, BD7 1DP, UK http://www.brad.ac.uk/life‐sciences/academic‐divisions/chemical‐and‐forensic‐sciences/
4. Laboratoire National des Champs Magnétiques Intenses, CNRS UPR 3228, 25 Rue des Martyrs, 38042 Grenoble, France