1. Department
of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
2. Department
of Chemistry, McNeese State University, Lake Charles, Louisiana 70609, United States
3. Department
of Physics, Konstanz University, 78457 Konstanz, Germany
4. Department
of Chemistry, University of Maryland, College Park, Maryland 20742, United States
5. Department of Physics, Florida A&M University, Tallahassee, Florida 32307, United States
6. Department
of Physics, Virginia Commonwealth University, Richmond, Virginia 23284, United States