On the generation of electronic ring currents under vibronic coupling effects

Area of Science:

• Quantum mechanics
• Physical chemistry
• Theoretical physics

Background:

• Electronic ring currents are fundamental to molecular magnetism and spectroscopy.
• Nonadiabatic coupling between electronic and nuclear motion is crucial in many photochemical processes.
• Understanding these phenomena requires sophisticated theoretical models.

Purpose of the Study:

• To investigate the generation of electronic ring currents under nonadiabatic coupling.
• To introduce and analyze a solvable model for electron-nuclear dynamics.
• To elucidate the role of vibronic coupling in current generation.

Main Methods:

• Development of a solvable model of an electron and nucleus with Coulomb interaction.
• Application of circularly polarized light to induce electronic dynamics.
• Analysis of the model in various limiting cases, including the Born-Oppenheimer limit.

Main Results:

• Vibronic coupling effects are critical for electronic ring currents, even in degenerate eigenstates.
• The maximum current in degenerate eigenstates is modulated by the strength of nonadiabatic interactions.
• In the heavy nucleus mass limit (Born-Oppenheimer approximation), currents vanish.

Conclusions:

• A solvable model reveals the non-trivial influence of nuclear coordinates on electronic ring currents.
• Vibronic coupling plays a decisive role in the magnitude and behavior of electronic ring currents.
• The study provides insights into the fundamental interplay between electronic and nuclear motion.