Rydberg-resolved resonant inelastic soft x-ray scattering: dynamics at core ionization thresholds

Area of Science:

• Atomic and Molecular Physics
• Quantum Chemistry
• Spectroscopy

Background:

• Core-level ionization and subsequent electronic relaxation are fundamental processes in molecules.
• Understanding excited states is crucial for predicting molecular behavior and reactivity.
• Resonant inelastic x-ray scattering (RIXS) offers a powerful probe of electronic structure.

Purpose of the Study:

• To investigate the electronic structure of N2 near core-level ionization thresholds.
• To characterize symmetry-selected Rydberg series and vibrational excitations in final states.
• To validate a quasi-two-step model for interpreting RIXS spectra.

Main Methods:

• Excitation of N2 using resonant inelastic x-ray scattering (RIXS) near nitrogen K-edge.
• High-resolution spectral analysis to resolve final states and Rydberg series.
• Theoretical modeling using a quasi-two-step approach.

Main Results:

• Well-resolved RIXS spectra showing symmetry-selected Rydberg series converging to valence ionization thresholds.
• Observation of vibrational excitations within these Rydberg series.
• Excellent agreement between experimental data and the quasi-two-step model.

Conclusions:

• The quasi-two-step model effectively simplifies RIXS spectral interpretation near ionization thresholds.
• RIXS is a valuable tool for characterizing low-energy excited final states in molecular systems.
• The study provides detailed insights into the electronic dynamics of N2 following core excitation.