1. Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom, Lawrence Livermore National Laboratory, Livermore, California 94550, Helmholtz Zentrum Berlin - BESSY II - Albert-Einstein-Str.15, 12489 Berlin, Germany, and Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom