| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2016) | |
| Nanomaterials | Tuesday Sessions |
| Session NM-TuM |
| Session: | Nanofabrication and Nanodevices I |
| Presenter: | Szymon Godlewski, Jagiellonian University, Poland |
| Authors: | S. Godlewski, Jagiellonian University, Poland M. Kolmer, Jagiellonian University, Poland M. Engelund, Donostia International Physics Center, Spain H. Kawai, Institute of Materials Research and Engineering R. Zuzak, Jagiellonian University, Poland A. Garcia-Lekue, Donostia International Physics Center, Spain A.M. Echavaren, Institute of Chemical Research of Catalonia D. Pena, Universidad de Santiago de Compostela D. Perez, Universidad de Santiago de Compostela E. Guitian, Universidad de Santiago de Compostela C. Joachim, CEMES-CNRS, France D. Sanchez-Portal, Donostia International Physics Center, Spain M. Saeys, Ghent University, Belgium M. Szymonski, Jagiellonian University, Poland |
| Correspondent: | Click to Email |
In recent years the on-surface, local chemistry attracts growing attention, inspired by the interest in fundamental processes occurring on surfaces, as well as by potential technological applications. In particular, the controlled and reversible bonding between single molecules and atoms could be advantageous in construction of prototypical molecular switches, rotors and electronic circuits. To control the electronic properties of organic species the isolation from the underlying substrate is required. This could be achieved by application of passivated surfaces that enable retention of originally designed properties [1-3]. Hydrogen passivated silicon and germanium surfaces are of particular interest enabling creation of atomic scale defects – hydrogen vacancies that could interact with organic molecules and form artificial wiring [4-5].
In the presentation we will demonstrate reversible Diels-Alder attachment of prototypical three-branch conjugated molecules to paired surface dangling bonds. We will show that molecules initially undergo the [4+2] cycloaddition forming chemical bonds with the unsaturated surface dangling bonds [6]. Further, it will be discussed that the bonds could be broken and restored using the low temperature scanning tunnelling microscope. We will demonstrate that at low temperature the molecules located on surface dangling bonds could be switched between the chemisorbed configuration and the physisorbed one held by van der Waals interactions only. Interestingly, the molecules adsorbed in the latter configuration could be controllably switched rotationally with the STM tip, which constitutes the first molecular switch on a passivated surface. Further it will be shown that by tuning the structure of the molecules the attachment geometry could be controlled with high selectivity. Finally we will introduce prospects for utilization of the control over connecting individual molecules with surface single atoms.
[1] Szymon Godlewski et al. ACS Nano 7 (2013) 10105–10111
[2] Amandine Bellec et al. Nano Lett. 9 (2009) 144–147.
[3] Szymon Godlewski et al. Phys. Chem. Chem. Phys. 18 (2016) 3854
[4] Marek Kolmer et al. Phys. Rev. B 86, 125307 (2012)
[5] Marek Kolmer et al. Nanoscale 7 (2015) 12325
[6] Szymon Godlewski et al. Phys. Chem. Chem. Phys. 2016, 18, 16757-16765
This research was supported by the National Science Centre, Poland (contract no. UMO-2014/15/D/ST3/02975) and the 7th Framework Programme of the European Union Collaborative Project PAMS (contract no.610446).