1. Dipartimento
di Scienza dei Materiali, Università degli Studi di Milano-Bicocca, via Cozzi 55, I-20125 Milano, Italy
2. Chemistry
Division and Center for Advanced Solar Photophysics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
3. École Polytechnique Fédérale de Lausanne (EPFL), 1015 CH Lausanne, Switzerland