1. Department of Chemistry, Jadavpur University, Kolkata 700 032, India E‐mail: m_ali2062@yahoo.com, http://www.jaduniv.edu.in/profile.php?uid=30
2. CNRS, CRPP, UPR 8641, 33600 Pessac, France
3. Univ. Bordeaux, CRPP, UPR 8641, 33600 Pessac, France
4. National Changhua University of Education, Department of Chemistry, Changhua 50058, Taiwan