1. School of Chemistry, Nottingham University, University Park, Nottingham, NG7 2RD, U.K., CLRC Daresbury Laboratory, Daresbury, Warrington, Cheshire, WA4 4AD, U.K., Delft University of Technology, Kluyver Department of Biotechnology, Julianalaan 67, 2628 BC Delft, The Netherlands, and European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble, France