1. Department of Chemistry, University of Tromsø, N-9037 Tromsø, Norway
2. Stanford Synchrotron Radiation Lightsource (SSRL), SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, United States
3. Department of Chemistry, University of the Free State, P.O. Box 339, Bloemfontein 9300, Republic of South Africa