1. Department of Chemistry, University of Bath, Bath BA2 7AX, U.K.
2. The Faraday Institution, Quad One, Harwell Science and Innovation Campus, Didcot OX11 0RA, U.K.
3. Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.
4. Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, U.K.
5. Thomas Young Centre, University College London, Gower Street, London WC1E 6BT, U.K.