Dissipative many-electron dynamics of ionizing systems.

Area of Science:

• Quantum chemistry
• Computational physics
• Molecular dynamics

Background:

• Simulating complex molecular systems requires accurate methods for many-electron dynamics.
• Incorporating dissipation and ionization effects is crucial for realistic modeling.
• Existing methods may face computational challenges with increasing system complexity.

Purpose of the Study:

• To develop and validate a novel computational method for simulating many-electron dynamics.
• To incorporate ionization effects into the reduced density matrix formulation of the time-dependent configuration-interaction method (ρ-TDCI).
• To improve the computational efficiency of simulating dissipative and ionizing quantum systems.

Main Methods:

• Extension of a heuristic model for ionizing states to the ρ-TDCI method.
• Implicit treatment of dissipation using the Lindblad formalism.
• Development of a modified scheme for treating ionizing states to reduce computational cost.

Main Results:

• The new method successfully models laser-driven excitation of H(2) in a dissipative environment.
• It accurately simulates laser-induced intramolecular charge transfer in a quinone derivative.
• The modified scheme shows favorable scaling (∼N^2) compared to the original model (∼N^3).

Conclusions:

• The developed ρ-TDCI method with an extended ionization model provides a powerful tool for studying quantum dynamics.
• The improved computational scaling makes it applicable to larger and more complex molecular systems.
• This work advances the simulation of realistic molecular processes, including those relevant to surface chemistry and molecular switches.