1. Dipartimento
di Scienze Chimiche, Università di Napoli Federico II, Complesso
Monte S. Angelo, Via Cintia, I-80126 Napoli, Italy
2. Department
of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, United States
3. Institut
Charles Sadron, CNRS-Université Louis Pasteur, 23 Rue du Lœss, 67034 Strasbourg, France