1. Nanotechnology, Academic Division of Industrial Mechanics, Emiliano Zapata Technological University of the State of Morelos, Emiliano Zapata 62765, Mexico
2. Spectroscopy Laboratory, Institute of Physical Sciences, National Autonomous University of Mexico, Av. Universidad #1000, Col. Chamilpa, Cuernavaca 62210, Mexico
3. Faculty of Chemistry, National Autonomous University of Mexico, Cuajimalpa 05000, Mexico