1. Physics Department and Center of Excellence for Nanostructured Materials (CENMAT), University of Trieste, Via A. Valerio 2, I-34127, Trieste, Italy, Laboratorio Nazionale CNR TASC-INFM, Area Science Park, SS 14 km 163.5, I-34012, Basovizza (TS), Italy, Chemistry Department, University of Trieste, Via L. Giorgieri 1, I-34127, Trieste, Italy; Italian Consortium on Materials Science and Technology (INSTM), Department of Theoretical Physics, University of Trieste, Strada Costiera 11, I-34014, Trieste, Italy,...