A size-consistent multi-state mapping approach to surface hopping

Area of Science:

• Computational Chemistry
• Quantum Dynamics
• Theoretical Chemistry

Background:

• Simulating electronically nonadiabatic dynamics is crucial for understanding chemical reactions.
• Existing methods often struggle with systems involving more than two electronic states.
• The mapping approach to surface hopping (MASH) is a recent advancement.

Purpose of the Study:

• To develop a multi-state generalization of the MASH method.
• To extend MASH for simulating systems with over two electronic states.
• To ensure the new method is size consistent and recovers the two-state MASH.

Main Methods:

• Developed a multi-state generalization of the mapping approach to surface hopping (MASH).
• Applied the new method to various model systems with known benchmark results.
• Focused on simulations of electronically nonadiabatic dynamics.

Main Results:

• The multi-state MASH method accurately simulates systems with multiple electronic states.
• The approach is size consistent.
• It rigorously recovers the original two-state MASH in the correct limits.
• Demonstrated accuracy against exact benchmark results.

Conclusions:

• The developed multi-state MASH is a powerful tool for simulating complex photochemical relaxation processes.
• This method provides a reliable approach for studying nonadiabatic dynamics in larger systems.
• The generalization maintains key advantages of the original MASH approach.