1. Departamento de Ingeniería Matemática and CI2 MA, Universidad de Concepción, Concepción, Casilla 160-C, Chile
2. Penn State Institute of Energy and the Environment, Pennsylvania State University, University Park, PA 16802, USA
3. Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA
4. Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16802, USA
5. Department of Physics, Lahore University of Management Sciences, Lahore 54792, Pakistan
6. Department of Mathematical Sciences, University of Delaware, Newark, DE 19716, USA