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Non-adiabatic molecular dynamics with complex quantum trajectories. II. The adiabatic representation
1Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
The Journal of Chemical Physics
|December 20, 2012
Summary
We developed a complex quantum trajectory method for non-adiabatic dynamics. This approach naturally incorporates decoherence without needing extra adjustments, showing excellent agreement with quantum calculations.
Area of Science:
- Quantum mechanics
- Chemical physics
- Computational chemistry
Background:
- Non-adiabatic dynamics are crucial in chemical reactions.
- Accurate simulation of these dynamics is computationally challenging.
- Existing methods often require approximations or ad hoc additions.
Purpose of the Study:
- To present a novel complex quantum trajectory method for non-adiabatic dynamics.
- To derive equations of motion in the adiabatic representation.
- To validate the method against benchmark models.
Main Methods:
- Utilizing complex position and momentum for trajectories evolving on single electronic surfaces.
- Deriving equations of motion directly from the time-dependent Schrödinger equation.
- Employing amplitude-transfer terms for population exchange.
Main Results:
- The method successfully treats non-adiabatic dynamics.
- Excellent agreement was achieved with converged quantum-mechanical calculations for benchmark models.
- Decoherence is shown to be an inherent feature of the derived equations.
Conclusions:
- The complex quantum trajectory method provides an accurate and efficient way to study non-adiabatic dynamics.
- The inherent inclusion of decoherence simplifies the treatment of quantum effects.
- This method offers a valuable tool for theoretical chemical dynamics.
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