1. a Department of Chemistry , Shibpur Dinobundhoo Institution (College) , 412/1 G.T. Road (South), Howrah – 711102 , India
2. b Chemical Sciences Division, Saha Institute of Nuclear Physics , 1/AF-Bidhannagar, Kolkata – 700064 , India
3. c Department of Chemistry , Jadavpur University , Raja S.C. Mullick Road, Kolkata – 700032 , India