1. Department of Chemistry, Clemson University, Clemson, South Carolina 29634, United States
2. Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, United States
3. Clemson Nanomaterials Institute, Clemson University, Clemson, South Carolina 29634, United States
4. Department of Chemistry, University of Central Florida, 4111 Libra Drive, Orlando, Florida 32816-2366, United States
5. Center for Optical Materials Science and Engineering Technology (COMSET) Clemson University, Clemson, South Carolina 29625, United States