1. School of Studies in Chemistry, Pt. Ravishankar Shukla University, Raipur (C.G.) 492010, India
2. Dipartimento di Chimica Generale ed Organica Applicata e Centro di Eccellenza NIS, Università degli Studi di Torino, Corso Massimo D’Azeglio 48, 10125 Torino, Italy
3. Centre for Surface Science, Department of Chemistry, Jadavpur University, Kolkata 700032, India