1. Division of Theoretical Chemistry, Faculty of Science, Vrije Universiteit Amsterdam, de Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
2. Netherlands eScience Center, Science Park 140 (Matrix I), 1098 XG Amsterdam, The Netherlands
3. Institute of Physical and Theoretical Chemistry, TU Braunschweig, Gaußstraße 17, 38106 Braunschweig, Germany
4. Department of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy