1. Physics Department, Illinois Institute of Technology, Chicago, Illinois 60616
2. Lawrence Berkley National Laboratory, Berkley, California 94720
3. European Synchrotron Radiation Facility, Grenoble 38000, France
4. GSECARS, University of Chicago, Argonne, Illinois 60439
5. X-Ray Science Department, Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439
6. Material Science Division, Argonne National Laboratory, Argonne, Illinois 60439
7. Commissariat de l'énergie atomique, Centre de Saclay, Gif-sur-Yvette 91191, France