1. Lawrence Livermore National
Laboratory, Livermore, California 94550, United States
2. Department of Physics, University
of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United
States
3. Princeton Center For
Theoretical
Science and Department of Physics, Joseph Henry Laboratories, Princeton
University, Princeton, New Jersey 08544, United States
4. National Center for Supercomputing
Applications, University of Illinois at Urbana−Champaign, Urbana,
Illinois 61801, United States and Materials Science and Technology
Division and Computational Chemistry and Materials Division, Oak Ridge
National Laboratory, Oak Ridge, Tennessee 37830, United States
5. Department of Chemistry and Department of Physics & Astronomy, Rice University, Houston, Texas 77005-1892, United States