1. Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.
2. X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, United States
3. Diamond Light Source, Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, U.K.
4. Johnson Matthey Technology Centre, Blount’s Court, Sonning Common, Reading RG4 9NH, U.K.