Design and Characterization of an Electrically Powered Single Molecule on Gold

Abstract

The surface diffusion of individual molecules is of paramount importance in self-assembly processes and catalytic processes. However, the fundamental understanding of molecule diffusion peculiarities considering conformations and adsorption sites remain poorly known at the atomic scale. Here, we probe the 4'-(4-tolyl)-2,2':6',2″-terpyridine adsorbed on the Au(111) herringbone structure combining scanning tunneling microscopy and atomic force microscopy. Molecules are controllably translated by electrons excitations over the reconstruction, except at elbows acting as pinning centers. Experimental data supported by theoretical calculations show the formation of coordination bonds between the molecule and Au atoms of the surface. Using force spectroscopy, we quantify local variation of the surface potential and the lateral force required to move the molecule. We found an elevation of the diffusion barrier at elbows of the reconstruction of ∼100 meV compared to the rest of the surface.

Recent highlights in nanoscale and mesoscale friction

“…As a consequence, a growing number of studies is now focusing on friction of sliding nano-objects, where well-defined interfaces are made accessible for structures prepared by thermal evaporation [ 44 – 48 ] or lithographic techniques [ 49 – 54 ]. Alternatively, molecular-scale structures such as PTCDA [ 55 ], polyfluorene chains [ 56 ], graphene nanoflakes on graphene [ 57 ] or graphene nanoribbons (GNRs) on single crystals [ 58 ] can be analyzed (see [ 59 ] for a detailed review on single-molecule manipulation in nanotribology). These experimental efforts are accompanied by increasing theoretical work, where the analysis of specific nanoscale systems and systematic variation of their key characteristics provides fundamental insight into a large variety of tribological phenomena.…”

“…The pilots from the University of Basel, Rémy Pawlak and Tobias Meier, were able to efficiently steer a single molecule along the 100 nm racetrack over a time of five hours, thus achieving an average speed of 20 nm/h. The Swiss team ranked first at this international competition, but most importantly some fundamental knowledge about the motion of single molecules on surfaces was gained, which is relevant for nanotribology [ 59 , 194 ]. For successfully “driving” a nanocar, a detailed understanding of the energetics of the molecule on different surface locations, which are closely related to atomic friction processes, is required.…”

Nano Trek Beyond: Driving Nanocars/Molecular Machines at Interfaces

“…The winner on the gold track was the Swiss Nano Dragster (Figure ) . This small car was designed to lie flat in valleys on the gold surface.…”

Inducing the controlled rotation of single o-MeO-DMBI molecules anchored on Au(111)

“…Introduction Scanning tunneling microscopy (STM) does not only allow to image conducting surfaces and molecular adsorbates with high spatial resolution, but provides a nanoscale probe able to manipulate matter at the atomic scale [1]. The STM tip can be used to induce chemical reactions [2,3], to translate [4], rotate [5], and switch single molecules [6,7], or to drive nanocars [8][9][10]. A pioneer in the field of manipulation and the control of single atoms and molecules using an STMtip was Karl-Heinz Rieder [11][12][13].…”