1. Università degli Studi di Cagliari, Dipartimento di Scienze Chimiche e Geologiche, 09042 Monserrato (Cagliari), Italy
2. EaStCHEM School of Chemistry, University of St. Andrews, North Haughs, St. Andrews, Fife KY16 9ST, U.K.
3. Department of Chemistry, Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates