In July 2023, Yuan Li’s group has designed a series of isomers of nitrogen-containing phenyl-decylthiol molecules. By altering the position of the nitrogen atom in the nitrogen-containing phenyl group, we achieved sub-nanometer-scale control over the molecular-electrode coupling strength. This resulted in five isomeric molecular devices with closely aligned energy levels exhibiting markedly different electrical characteristics, transitioning from pure resistance (rectification ratio of 1) to high-performance molecular diodes (rectification ratio exceeding 200).