1. Department of Chemistry; Raghunathpur College; Purulia 723 133,West Bengal India
2. Department of Chemical Sciences; Indian Institute of Science Education and Research, S.A.S. Nagar, Sector 81, Manauli PO; Mohali 140 306 India
3. Department of Chemistry; National Institute of Technology; Durgapur 713209, West Bengal India
4. Present Address: Department of Chemistry; Surendranath College; 24/2 M.G. Road, Kolkata 700009, West Bengal India