1. Department of Chemistry, Jadavpur
University, Kolkata 700 032, India
2. Department of Physics, M. G.
Mahavidyalaya, Bhupatinagar, Midnapore (East), West Bengal 721 425,
India
3. School of Chemistry,
The University
of Manchester, Brunswick Street, Manchester, M13 9PL, United Kingdom
4. Departament de Química,
Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122
Palma (Baleares), Spain