1. Department of Chemistry, University of Calcutta, Kolkata, India
2. Department of Chemistry, Acharya Prafulla Chandra College, Kolkata, India
3. Department of Physics, Behala College, Kolkata, India
4. Departamento de Química Físicay Analítica, Universidad de Oviedo, Oviedo, Spain
5. Department of Chemistry, University of Kalyani, Kalyani, India