1. Dipartimento di Scienze Chimiche e Farmaceutiche, Università di Trieste, Via Giorgieri 1, I-34127 Trieste, Italy
2. CNR-ICCOM & IPCF, Consiglio Nazionale delle Ricerche, Via Giuseppe Moruzzi 1, I-56124 Pisa, Italy
3. Department of Chemistry, University of Padova, Via Marzolo 1, I-35131 Padova, Italy
4. Department of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut 06269, USA