1. Institut für Chemie, Theoretische Chemie/Quantenchemie, Technische Universität Berlin, Sekr. C7, Straße des 17. Juni 135, D-10623 Berlin, Germany
2. Department of Chemistry, Faculty of Science, University of Helsinki, P.O. Box 55
(A.I. Virtanens plats 1), University of Helsinki FI-00014, Finland
3. Molecular Sciences Software Institute, Blacksburg, Virginia 24061, United States