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

TL;DR

This study demonstrates the controlled, stepwise rotation of single o-MeO-DMBI molecules on Au(111) surfaces using tunneling electrons from a scanning tunneling microscope, advancing single molecule machine development.

Contribution

It introduces a method to induce and control the unidirectional rotation of complex molecules on surfaces via inelastic tunneling electrons.

Findings

Molecules chemisorb on Au(111) via oxygen-gold bonds.

Controlled rotation is achievable with tunneling electrons.

Rotation direction depends on molecular enantiomeric form.

Abstract

A key step towards building single molecule machines is to control the rotation of molecules and nanostructures step by step on a surface. Here, we used the tunneling electrons coming from the tip of a scanning tunneling microscope to achieve the controlled directed rotation of complex o-MeO-DMBI molecules. We studied the adsorption of single o-MeO-DMBI molecules on Au(111) by scanning tunneling microscopy at low temperature. The enantiomeric form of the molecule on the surface can be determined by imaging the molecule by STM at high bias voltage. We observed by lateral manipulation experiments that the molecules chemisorb on the surface and are anchored on Au(111) with an oxygen-gold bond via their methoxy-group. Driven by inelastic tunneling electrons, o-MeO-DMBI molecules can controllably rotate, stepwise and unidirectional, either clockwise or counterclockwise depending on their enantiomeric form.