1. Institute of Molecule and Crystal Physics,
Ufa Research Centre, Russian Academy of Sciences, Prospekt Oktyabrya
151, 450075 Ufa, Russia
2. Physics Faculty, St. Petersburg State University, Uljanovskaja 1, 198504 St. Petersburg, Russia
3. Dipartimento
di Chimica “G. Ciamician”, Università di Bologna, via Selmi 2, 40126 Bologna, Italy
4. Centro Interdipartimentale di Ricerca in Scienze Ambientali, via S. Alberto 163, 48123 Ravenna, Italy