On the possibility of exploring tip-molecule interactions with STM experiments

TL;DR

This paper develops a theoretical framework to analyze how molecules interact with STM tips by examining residence times, enabling estimation of interaction types and strengths, and applicable to various single-molecule experimental probes.

Contribution

The paper introduces a novel theory for analyzing tip-molecule interactions in STM, applicable to one- and two-dimensional diffusion, and capable of estimating interaction parameters.

Findings

Derived explicit results for harmonic tip-molecule interactions.

The theory can estimate interaction strength and type from residence time data.

Applicable to other single-molecule experimental techniques.

Abstract

We present a theory for analyzing residence times of single molecules in a fixed detection area of a scanning tunneling microscope (STM). The approach is developed for one-dimensional molecule diffusion and can be extended to two dimensions by using the same methodology. Explicit results are derived for an harmonic attractive and repulsive tip-molecule interaction. Applications of the theory allows one to estimate the type and strength of interactions between the STM tip and the molecule. This includes the possibility of an estimation of molecule-molecule interaction when the tip is decorated by a molecule. Despite our focus on STM, this theory can analogously be applied to other experimental probes that monitor single molecules.