1. Physics Department, Faculty of Science, University of Hail, Kingdom of Saudi Arabia
2. Laboratoire de Physique de la
Matière Condensée, Département de
Physique, Faculté des Sciences de Tunis, Campus universitaire, 1060 Tunis, Tunisia
3. Department of Chemistry, University of Alberta, Gunning/Lemieux
Chemistry Centre, 11227 Saskatchewan Drive, Edmonton, Canada T6G 2G2
4. On leave from: Laboratoire de
Physique Quantique, Faculté des Sciences de Monastir, route
de Kairouan, 5000 Monastir, Tunisia