1. Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, Blindern, Oslo, Norway;
2. Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study, Massey University Auckland, Auckland, New Zealand;
3. Department of Chemistry, University of Helsinki, Helsinki, Finland;
4. Niels Bohr Institute, University of Copenhagen (NBI), Copenhagen, Denmark;
5. Department of Computer Science, University of Copenhagen (DIKU), Copenhagen, Denmark