1. European Laboratory for Non-Linear Spectroscopy (LENS) Via Nello Carrara, 1 50019 Sesto Fiorentino Florence) Italy
2. National Institute of Optics-National Research Council (INO-CNR) Via Madonna del Piano 10 50019 Sesto Fiorentino (Florence) Italy
3. Istituto Pasteur-Fondazione Cenci Bolognetti and Dipartimento di Scienze Biochimiche Università “Sapienza” di Roma P. Aldo Moro 5 00185 Rome Italy
4. Department of Chemistry Ugo Schiff University of Florence Via Della Lastruccia 3–13 50019 Sesto Fiorentino Florence) Italy
5. Department of Chemistry University of Perugia Via Elce di sotto 8 06100 Perugia Italy