1. Molecular Electronics, Department of Electrical and Computer Engineering, Technical University of Munich, Theresienstraße 90, 80333 Munich, Germany
2. Department of Chemistry, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching, Germany
3. Department of Chemistry, Ludwig-Maximilians-University, Butenandtstr 5-13, 81377 Munich, Germany
4. Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
5. Center for NanoScience (CeNS), Ludwig-Maximilians-University, Geschwister-Scholl Platz 1, 80539 Munich, Germany
6. Fraunhofer Research Institution for Microsystems and Solid State Technologies (EMFT), Hansastrasse 27d, 80686 Munich, Germany