Adsorbate Motors: Tricking Microscopic Reversibility on Surfaces

Introduction

AMOS represents a ground-breaking approach to achieve uni-directional motion on well-defined surfaces, realize cooperative motor activity, control flow processes, and transport cargo at the atomic scale. It is based on molecule-surface motors that overcome microscopic reversibility via controlled potential energy surface modulation with high potential impact in various fields.

Methodology

Light will be used to excite molecular motion, offering great versatility. Hence, the stimulus is given remotely to many molecules, while characterization is done at the single-molecule level, allowing for statistical analysis of trajectories in two dimensions.

Motor Concepts

Different motor concepts will be used to controllably modulate the potential energy surfaces and address the key challenges in the field of molecular machines at surfaces. A variety of highly defined surfaces will be employed, and novel adsorbate motors, molecules that achieve motor functionality only when joined together with a surface, will be studied.

Advanced Control

Advanced control of motion will be achieved by multiple motors. Complementary methods in microscopy, spectroscopy, and interferometry with extremely high resolution in space, energy, and time will be used – a key aspect of this project.

Research Goals

AMOS addresses both fundamental research and technological aspects:

1. It will yield elementary understanding of molecular motors with extremely high spatial (pm) and temporal (fs) resolution.
2. It will investigate model systems for future applications with insight at the single-molecule level.
3. It will explore collectivity to amplify motor activity by cooperative effects in precisely defined assemblies.
4. It will study these systems also under environmental conditions in view of steered flow processes at the solid-liquid interface.

Transport Mechanisms

Specific chemical interactions will realize transport and delivery of single or few atoms cargo with individual motor molecules, a fundamental step towards bottom-up construction of matter by molecular machines.