1. Department of Chemistry & Biochemistry, The University of Texas at Arlington, Arlington, Texas 76109-0065, United States
2. Department of Physics, The University of Texas at Arlington, Arlington, Texas 76109-0065, United States
3. Department of Applied Physics, CINVESTAV-IPN, Merida, Yucatán. 97310, Mexico
4. Department of Chemistry and Biochemistry, Louisiana State University, Baton Rouge, Louisiana 70803-2804, United States
5. Departamento de Sistemas Fı́sicos, Quı́micos y Naturales, Universidad Pablo de Olavide, Sevilla 41013, Spain