1. Department
of Chemistry and Applied Biosciences, ETH Zurich and Università della Svizzera Italiana, via G. Buffi 13, CH-6900 Lugano, Switzerland
2. The Abdus Salaam International Center for Theoretical Physics, Condensed Matter Physics Section, Strada Costiera 11, I-34151 Trieste, Italy
3. Laboratory of Computational
Science and Modeling, IMX, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland