1. Combustion Research Facility, Mailstop 9055, Sandia National Laboratories, Livermore, California, 94551-0969, Departments of Chemistry and Physics, and Lawrence Berkeley National Laboratory, University of California, Berkeley, California, 94720, Department of Chemistry, University of Southern California, Los Angeles, California, 90089-0482, and Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, California, 90089-1453