1. Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan
2. Department of Physics, University of Sargodha, Sargodha, Pakistan
3. Instituto de Química, Universidade Federal da Bahia – UFBA, Salvador, Brazil
4. Departamento de Fisica, Universidade Federal de Santa Catarina – UFSC, Florianópolis, Brazil