1. School of Chemistry and Photon Science Institute; The University of Manchester; Oxford Road Manchester M13 9PL UK
2. Institut Laue-Langevin, BP 156; 6 rue Jules Horowitz 38042 Grenoble Cedex 9 France
3. Department of Physics; Durham University; South Road Durham DH1 3LE UK
4. Dipartimento di Fisica e Scienze della Terra; Università di Parma; 43124 Parma Italy
5. ISIS Facility; Rutherford Appleton Laboratory; Didcot OX11 0QX UK
6. Clarendon Laboratory; Department of Physics; University of Oxford; OX1 3PU UK
7. Department of Chemistry and Biochemistry; University of Bern; 3000 Bern Switzerland