Academic Affiliation: IBM Research

Talk: November 5, 2018

On-surface synthesis by atom manipulation studied with atomic force microscopy

Elusive molecules can be created using atom manipulation with a combined atomic force/scanning tunneling microscope (AFM/STM). Molecules that are highly reactive and shortlived under ambient conditions can be stabilized at low temperature and by using inert surfaces. Employing high-resolution AFM with functionalized tips [1] provides insights into the structure, geometry, aromaticity and bond orders of the molecules created and into the reactions performed [2].

We created radicals, diradicals [3], non-Kekulé molecules [4], anti-aromatics [5], and polyynes [6] and studied their structural and electronic properties. We expanded the toolbox for the synthesis of molecules by atom manipulation, demonstrating reversible cyclisation reactions [3] and, most recently, skeletal rearrangements (see figure) [6]

Figure: Polyyne formation via a skeletal rearrangement induced by atom manipulation. Chemical reaction scheme (top). CO-tip AFM data (bottom), showing the different reaction steps on bilayer NaCl on Cu(111). All reaction steps are induced by bias voltage pulses with the AFM tip. [6]

Reference:
[1] L. Gross et al. Science 325, 1110 (2009)
[2] L. Gross et al. Angew. Chem. Int. Ed 57, 3888 (2018)
[3] B. Schuler et al. Nat. Chem. 8, 220 (2016)
[4] N. Pavliček et al. Nat. Nano. 12, 308 (2017)
[5] Z. Majzik et al. Nat. Comm. 9, 1198 (2018)
[6] N. Pavliček et al. Nat. Chem. 10, 853 (2018)