a
Empa, Swiss Federal Laboratories for Materials Testing and Research, nanotech@surfaces Laboratory, Feuerwerkerstrasse 39, 3602 Thun, Switzerland
E-mail: marco.bieri@empa.ch; roman.fasel@empa.ch
;
Fax: +41 44 823 40 34
;
Tel: +41 44 823 43 48
b
Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
c
Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland