1. Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
2. Department of Physics, Stockholm University, SE-10691 Stockholm, Sweden
3. Department of Physics and Astronomy, Aarhus University, Aarhus 8000, Denmark
4. School of Chemistry, Norwich Research Park, University of East Anglia, Norwich NR4 7TJ, United Kingdom
5. Institut de Química Computacional i Catálisi and Departament de Química, Universitat de Girona, C/M.A. Capmany 69, 17003 Girona, Spain