Photoionization from the Xe 4d orbitals of XeF₂

Area of Science:

• Atomic and molecular physics
• Quantum chemistry
• Spectroscopy

Background:

• The 4d shell photoionization of atomic Xenon (Xe) is a well-studied phenomenon.
• Understanding molecular systems like Xenon difluoride (XeF₂) provides insights into how chemical bonding affects electronic structure and dynamics.
• Comparing XeF₂ to atomic Xe allows for the isolation of molecular effects on photoionization.

Purpose of the Study:

• To compare the 4d shell photoionization dynamics of XeF₂ with atomic Xe.
• To investigate the influence of molecular environment and bonding on photoionization processes.
• To provide detailed experimental data and theoretical analysis of XeF₂ photoionization.

Main Methods:

• High-resolution synchrotron-based photoelectron spectroscopy.
• Measurement of partial cross sections, photoelectron angular distributions, and branching fractions.
• First-principles theoretical calculations for XeF₂.

Main Results:

• Spin-orbit branching fractions and angular distributions in XeF₂ closely resemble those of atomic Xe, even near resonances.
• Experimental data for XeF₂ show good agreement with theoretical calculations.
• Lifetime widths of 4d-hole states in XeF₂ are smaller than previously reported, suggesting a reevaluation of decay mechanisms.
• Auger electron and resonant Auger spectra provide further insights into ionization dynamics.

Conclusions:

• Molecular effects on 4d photoionization in XeF₂ are less pronounced than anticipated, particularly concerning spin-orbit and angular distributions.
• The observed linewidths necessitate a revised understanding of autoionization and decay pathways in XeF₂.
• This study offers a comprehensive dataset and analysis for XeF₂, contributing to the understanding of photoionization in molecules.