Coupled-trajectory surface hopping with sign consistency.

Area of Science:

• Computational Chemistry
• Quantum Dynamics
• Theoretical Chemistry

Background:

• The Exact Factorization (XF) framework has led to various trajectory-based nonadiabatic dynamics methods.
• Coupled-Trajectory Surface Hopping (CTSH) combines advantages of XF-based mixed quantum-classical methods and fewest switches surface hopping.

Purpose of the Study:

• To introduce a novel variant of CTSH, named Sign-Consistent CTSH (SC-CTSH).
• To enhance the accuracy and reliability of nonadiabatic dynamics simulations by improving trajectory clustering and wave function-active state consistency.

Main Methods:

• Developed Sign-Consistent CTSH (SC-CTSH) by incorporating trajectory clustering for nuclear density reconstruction.
• Introduced decoherence through consistent treatment of wave function and active states.
• Benchmarked SC-CTSH against exact quantum solutions using scattering models and compared with other XF-based methods.

Main Results:

• SC-CTSH demonstrates high performance in simulating nonadiabatic dynamics.
• The method achieves more accurate quantum momentum and decoherence compared to existing XF-based approaches.
• Improved trajectory clustering and sign consistency lead to a more reliable combination of XF and surface hopping.

Conclusions:

• SC-CTSH offers a more consistent and reliable approach for simulating nonadiabatic dynamics.
• The study underscores the importance of internal consistency between wave function and active states in mixed quantum-classical methods.
• This work contributes to the advancement of theoretical methods for studying quantum dynamics.