1. Centre for Theoretical Chemistry and Physics; The New Zealand Institute for Advanced Study, Massey University Auckland; Private Bag 102904 0745 Auckland New Zealand
2. Fachbereich Chemie; Philipps-Universität Marburg; Hans-Meerwein-Str. D-35032 Marburg Germany
3. Centre for Science at Extreme Conditions and SUPA, School of Physics and Astronomy; The University of Edinburgh; Edinburgh EH9 3FD United Kingdom
4. Mulliken Center for Theoretical Chemistry; University of Bonn, Beringstr. 4; 53115 Bonn Germany
5. Centre for Theoretical Chemistry and Physics; The New Zealand Institute for Advanced Study; Massey University Auckland, Private Bag 102904 0745 Auckland New Zealand
6. Fachbereich Chemie, Philipps-Universität Marburg; Hans-Meerwein-Str.; D-35032 Marburg Germany