Directed rotations of single porphyrin molecules controlled by localized force spectroscopy.
Directed molecular repositioning is a key step toward the build up of molecular machines. To artificially generate and control the motion of molecules on a surface, excitations by light, chemical, or electrical energy have been demonstrated. Here, the application of local mechanical forces is implemented to achieve directed rotations of molecules. Three-dimensional force spectroscopy with sub-Ångström precision is used to characterize porphyrin derivatives with peripheral carbonitrile groups. Extremely small areas on these molecules (≈ 100 × 100 pm(2)) are revealed which can be used to control rotations. In response to the local mechanical forces, the molecular structure elastically deforms and then changes its conformation, which leads to its rotation. Depending on the selection of one of four submolecular areas, the molecule is either rotated clockwise or counterclockwise.
Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland. remy.pawlak@unibas.ch
Rémy
R
Pawlak
Sweetlana
S
Fremy
Shigeki
S
Kawai
Thilo
T
Glatzel
Hongjuan
H
Fang
Leslie-Anne
LA
Fendt
François
F
Diederich
Ernst
E
Meyer
D016252:Microscopy, Scanning Tunneling; D015394:Molecular Structure; D009038:Motion; D049329:Nanostructures / Q000737:chemistry / Q000648:ultrastructure; D036103:Nanotechnology; D011166:Porphyrins / Q000737:chemistry; D012399:Rotation; D013057:Spectrum Analysis
D011166:Porphyrins