Stimulated X-ray Raman Imaging of Conical Intersections

Area of Science:

• Quantum Chemistry
• Molecular Dynamics
• Spectroscopy

Background:

• Conical intersections are critical in photochemistry and molecular dynamics.
• Understanding these dynamics is essential for controlling chemical reactions.
• Thiophenol serves as a model system for studying these phenomena.

Purpose of the Study:

• To theoretically investigate the conical intersection dynamics of thiophenol.
• To demonstrate the capability of stimulated X-ray Raman imaging (SXRI) for real-time molecular imaging.
• To differentiate between specific conical intersection pathways in thiophenol.

Main Methods:

• Theoretical study employing the stimulated X-ray Raman imaging (SXRI) technique.
• Utilizing a hard X-ray narrowband/broadband hybrid probe field.
• Calculating signals via the minimal-coupling radiation/matter Hamiltonian.
• Reconstructing real-space images of transition charge density using Fourier transforms.

Main Results:

• SXRI provides real-time and real-space imaging of passage through conical intersections.
• Phase information is encoded in the calculated signal.
• Distinct diffraction patterns were observed for the S2/S1 and S1/S0 conical intersections.
• The two conical intersections were successfully distinguished and identified.

Conclusions:

• SXRI is a powerful technique for visualizing ultrafast molecular dynamics.
• The study successfully identified and differentiated conical intersections in thiophenol.
• This work provides a theoretical framework for interpreting SXRI experiments in molecular systems.