1. Department of Chemistry, Quaid-i-Azam University, Islamabad-45320, Pakistan
2. Department of Chemistry, College of Science, University of Basrah, Basrah, Iraq
3. Department of Chemistry, College of Education, University of Qadisiya, Qadisiya, Iraq
4. Department of Chemistry, University of Otago, P. O. Box 56, Dunedin 9054, New Zealand