1. Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, USA
2. Laboratori Nazionali di Frascati-INFN, P.O. Box 13, 00044 Frascati, Italy
3. Department of Chemistry, Stanford University, Stanford, California 94305, USA
4. SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, USA
5. CINECA, SCAI—SuperComputing Applications and Innovation Department, Via dei Tizii 6, 00185 Roma, Italy