1. Department
of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg
1-5 CH-8093 Zurich, Switzerland
2. Faculty
of Informatics, Università della Svizzera Italiana, Via
G. Buffi 13, CH-6900 Lugano, Switzerland
3. Department
of Civil, Environmental and Geomatic Engineering, ETH Zurich, CH-8903 Zurich, Switzerland
4. Lehrstuhl
für Theoretische Chemie, Ruhr-Universität Bochum, Universitätsstrasse
150, D-44780 Bochum, Germany, and
5. Dipartimento
di Scienza dei Materiali, Università di Milano-Bicocca, Via
R. Cozzi 53, I-20125 Milano, Italy