Identifying the Conformational Isomers of Single-Molecule Cyclohexane at Room Temperature

Abstract

Conformational isomer is a fundamental concept in chemistry, providing the essential view to understand their unique role in molecular biology, medicine, and supramolecular chemistry. However, the interconversion between conformational isomers of the flexible molecule is fast at room temperature, and ensemble methods could only reflect the average contribution from all the conformational isomers, suggesting a significant challenge to distinguish corresponding isomers individually. In this work, we develop a single-molecule method to quantificationally identify the chair isomers of cyclohexane at room temperature beyond ensemble methods. We also demonstrate that the confinement effect of the attaching of electrodes to molecules could help in stabilizing and characterizing the twist-boat intermediate of cyclohexane. Our study provides a promising strategy to study the conformational isomers of flexible molecules and offers an insight into the fields, where flexible molecules play a role.