Stereoelectronic Switches of Single-Molecule Junctions through Conformation-Modulated Intramolecular Coupling...

Area of Science:

• Molecular Electronics
• Organic Chemistry
• Quantum Chemistry

Background:

• Single-molecule junctions are crucial for molecular switches, but achieving high efficiency and reproducibility remains a challenge.
• Stereoelectronic effects are key to molecular switching, yet controlling them for practical applications requires further investigation.

Purpose of the Study:

• To investigate the potential of 9,10-diphenyl-9,10-methanoanthracen-11-one (DPMAO) molecules for creating high-efficiency molecular switches.
• To explore how intramolecular conformations and electronic coupling influence molecular conductance in DPMAO junctions.

Main Methods:

• Theoretical calculations were employed to analyze the stable intramolecular conformations of DPMAO.
• The study examined electronic coupling (through-space, decoupling, through-bond) in different DPMAO conformations.
• The influence of solvent effects and external electric fields on molecular conformation populations was investigated.

Main Results:

• Three stable intramolecular conformations of DPMAO were identified, arising from steric effects.
• These conformations exhibited distinct electronic coupling mechanisms and molecular conductance values differing by over an order of magnitude.
• Conformation populations were found to be sensitive to solvent and external electric fields.

Conclusions:

• DPMAO molecule junctions, controlled by external stimuli, can function as efficient molecular switches.
• Modulating intramolecular electronic coupling is a viable strategy for designing molecular switches with high switching ratios.
• This research presents a novel approach for developing high-efficiency molecular switches in single-molecule junctions.