1. Institute of Physical and Theoretical Chemistry; Goethe University; Max-von-Laue-Str. 7 60438 Frankfurt am Main Germany
2. Interdisciplinary Center for Scientific Computing, IWR; University of Heidelberg; Im Neuenheimer Feld 205 69120 Heidelberg Germany
3. Institute of Organic Chemistry; Justus Liebig University; Heinrich-Buff-Ring 17 35392 Giessen Germany