1. Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan;
2. Centre for Advanced Drug Research, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, Pakistan;
3. Department of Chemistry, Allama Iqbal Open University, Islamabad, Pakistan;
4. Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA;
5. Department of Physics, University of Sargodha, Sargodha, Pakistan