1. Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Ave., Mellon Hall 302a, Pittsburgh, Pennsylvania 15282, United States
2. School of Resources and Chemical Engineering, Sanming University, 25 Jingdong Rd., Sanming, Fujian 365004, P. R. China
3. Department of Physics, Sogang University, Seoul 04017, South Korea
4. Centro Nacional de Tecnologías Ópticas (CNTO), Mérida 5101, Venezuela