1. Dipartimento di Chimica “G. Ciamician”, Università di Bologna, Bologna, Italy
2. Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
3. Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, CA, USA
4. Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, Blindern, Oslo, Norway
5. Department of Chemistry – Ångström, The Theoretical Chemistry Programme, Uppsala University, Uppsala, Sweden
6. Uppsala Center for Computational Chemistry – UC3, Uppsala University, Uppsala, Sweden