AG Raster - Tunnelmikroskopie



Prof. Dr. phil. Richard Berndt



Conductance of a molecular wire


Plenty of publications report on the conductance of molecular wires between electrodes. Characterization of the junction geometry, however, is usually missing. We synthesized a molecule for low-temperature STM experiments that stands vertically on a substrate. Despite this reductionist approach, its conductance data turned out to be
complex. Calculations show that geometrical changes, orbital symmetries, and bond formation control the conductance. This joint work within SFB677 by
Torben Jasper-Tönnies, Aran Garcia-Lekue, Thomas Frederiksen, Sandra Ulrich, Rainer Herges, and Richard Berndt has recently been published in Physical Review Letters and highlighted as Editors' Selection.

Gaede Preis 2017 for Dr. Guillaume Schull


At the meeting of the condensed matter division of the German Physical Society Dr. Guillaume Schull will be awarded the Gaede Preis 2017 for the work performed in the Berndt group.

''Dr. Guillaume Schull wird ausgezeichnet für seine wegweisenden experimentellen Untersuchungen an elektrischen Kontakten zu einzelnen Molekülen und Atomen sowie zur Emission von Licht aus solchen Kontakten.''

Cooperation with successful postdoc of SFB 677 continues at international level


Although Yong-Feng Wang left Kiel University five years ago the cooperation with the colleagues from the SFB 677 and the group of Professor Richard Berndt at the Institute of Experimental and Applied Physics still continues. Most recently a joint paper about the vacuum synthesis was published as a cover story of the journal Chemical Communications. Since 2006 Wang worked as a postdoc in the group of Professor Berndt and was involved in numerous publications. 2012 Wang went to Peking University, by now he leads a group at the Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics himself.

In their paper the international group of scientists present tunneling microscopy and spectroscopy data from magnetic magnetic aluminum phthalocyanine (AlPc) which was prepared in ultrahigh vacuum using on-surface metalation from H2Pc. It turns out that AlPc remains paramagnetic on Au(111) with its spin density distributed over the isoindole lobes. “The vacuum synthesis is a powerful method to synthesize air-unstable molecules like the magnetic AlPc molecules we synthesised in our paper”, Wang explains. “In vacuum, the effect by air reactive molecules such as oxygen and water can be excluded.”

“Results like these show how international successful the early career scientists of our Collaborative Research Center are. I am very glad the cooperation with Yong-Feng Wang continues despite the distance between Peking and Kiel”, says Richard Berndt. “My time in Kiel was the most important period in my scientific career“, Wang sums up. “Here I learnt how to find important scientific questions, how to solve them, how to make high-quality scientific figures, and how to write high-level papers.” Since he left Kiel Wang came back for two longer research stays to work with Berndt again. In future, he hopes to set up an international cooperative lab to continue their collaborative work.

Original publication:

Vacuum synthesis of magnetic aluminum phthalocyanine on Au(111) I-Po Hong, Na Li, Ya-Jie Zhang, Hao Wang, Huan-Jun Song, Mei-Lin Bai, Xiong Zhou, Jian-Long Li, Gao-Chen Gu, Xue Zhang, Min Chen, J. Michael Gottfried, Dong Wang, Jing-Tao Lü, Lian-Mao Peng, Shi-Min Hou, Richard Berndt, Kai Wu and Yong-Feng Wang, Chem. Commun., 2016, 52, 10338-10341. DOI: 10.1039/C6CC03359H