Time-resolved photoelectron spectra of CS2: dynamics at conical intersections.

Area of Science:

• Quantum chemistry
• Molecular dynamics
• Spectroscopy

Background:

• Conical intersections are crucial in polyatomic molecules, influencing reaction pathways.
• Simulating ultrafast dynamics around these intersections is computationally challenging.
• Understanding nuclear and electronic dynamics is key to controlling chemical reactions.

Purpose of the Study:

• To apply and validate a novel ab initio approach for simulating time-resolved molecular dynamics.
• To investigate nuclear and photoionization dynamics around conical intersections in CS2.
• To compare simulation results with experimental photoelectron angular distributions.

Main Methods:

• Utilizing a fully ab initio approach.
• Employing the multiple spawning method to obtain wave packet densities.
• Incorporating geometry- and energy-dependent photoionization matrix elements.

Main Results:

• Successfully simulated time-resolved molecular-frame photoelectron angular distributions for CS2.
• Achieved robust agreement between calculated and measured angular distributions.
• Demonstrated the technique's ability to disentangle nuclear and photoionization dynamics.

Conclusions:

• The developed ab initio technique accurately models molecular dynamics around conical intersections.
• This method provides a powerful tool for elucidating complex photochemical processes.
• The findings validate the approach for studying polyatomic molecules.