1. Department of Chemistry and Biochemistry, University of Texas at El Paso, El Paso, Texas 79968, USA
2. Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, USA
3. Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
4. Department of Physics, Illinois Institute of Technology, Chicago, IL, 60616, USA