1. Department for Organic Chemistry and Macromolecular Chemistry; Heinrich-Heine-Universität; Universitätsstraße 1 40225 Düsseldorf Germany
2. Department of Numerical Mathematics; Zuse Institute Berlin (ZIB); Takustr. 7 14195 Berlin Germany
3. Department of Mathematics and Computer Science; Freie Universität Berlin; Arnimallee 6 14195 Berlin Germany
4. Otto Diels Institute of Organic Chemistry; Christiana Albertina University of Kiel; Otto-Hahn-Platz 3-4 24118 Kiel Germany