1. Magnetic Resonance Center CERM, University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino Florence Italy
2. Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino Florence Italy
3. Department of Chemistry University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino Florence Italy