The destabilization of hydrogen bonds in an external E-field for improved switch performance

Area of Science:

• Computational chemistry
• Molecular electronics
• Quantum chemistry

Background:

• Molecular switches are crucial for developing advanced electronic devices.
• Understanding the influence of external stimuli on molecular switches is essential for their design.
• Quinone analogues have been proposed as potential molecular switch candidates.

Purpose of the Study:

• To investigate the effect of external electric fields on a quinone analogue-based molecular switch.
• To analyze the performance enhancement of the molecular switch's "ON" and "OFF" states.
• To explore the underlying mechanisms using advanced quantum chemical methods.

Main Methods:

• Utilized the Quantum Theory of Atoms in Molecules (QTAIM) methodology.
• Simulated the behavior of the molecular switch under homogenous external electric fields.
• Analyzed the electronic charge density and stress tensor properties.

Main Results:

• Reversing the external electric field improved the "OFF" state by destabilizing the tautomerizing H atom.
• The "ON" state performance was also enhanced by field reversal, a previously inaccessible result.
• Visualizations showed charge density motion responding to the electric field, consistent with QTAIM and stress tensor data.

Conclusions:

• External electric fields can be used to tune and improve molecular switch functionality.
• The QTAIM methodology provides consistent insights into switch performance factors.
• This research offers valuable guidance for the future design of molecular electronic devices.