Electron Dynamics upon Ionization of Polyatomic Molecules: Coupling to Quantum Nuclear Motion and Decoherence

Area of Science:

• Quantum Chemistry
• Molecular Dynamics
• Attosecond Science

Background:

• Electronic motion in molecules is crucial for understanding chemical reactions and biological processes.
• Attosecond techniques enable real-time observation and potential control of electronic motion.
• Factors influencing electronic decoherence and the role of nuclear motion are not fully understood.

Purpose of the Study:

• To investigate the factors influencing electronic decoherence in polyatomic molecules.
• To elucidate the role of nuclear motion in the electronic decoherence process.
• To provide insights into the dynamics of electronic motion using advanced simulation methods.

Main Methods:

• Quantum mechanical simulation of electron and nuclear dynamics.
• Utilized the direct dynamics variational multiconfigurational Gaussian (DD-vMCG) method.
• Simulated ionization dynamics in paraxylene and modified bismethylene-adamantane.

Main Results:

• Electronic decoherence occurs on a femtosecond timescale.
• Dephasing is identified as the primary driver of fast electronic decoherence.
• Nuclear overlap decay contributes to decoherence and can induce revivals.

Conclusions:

• The study provides significant physical insights into electronic decoherence mechanisms.
• Nuclear motion plays a complex role, both contributing to and potentially mitigating decoherence.
• Understanding these dynamics is vital for controlling molecular processes at the electronic level.