1. Computational Science, Department of Chemistry and Applied Biosciences, ETHZ Zurich USI-Campus, Via Giuseppe Buffi 13 C-6900 Lugano, Switzerland, CEA, DEN, Service de Recherches de Métallurgie Physique, F-91191 Gif-sur-Yvette, France, and Polymer Research, BASF SE, D-67056 Ludwigshafen, Germany