1. Department
of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
2. X-ray
Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States
3. Department of Physiology & Biophysics, University of California Irvine, Irvine, California 92697, United States
4. Spallation
Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
5. Department
of Chemistry, University of California Irvine, Irvine, California 92697, United States