Multi-reference protocol for (auto)ionization spectra: Application to molecules.

Area of Science:

• Atomic and Molecular Physics
• Quantum Chemistry
• Computational Spectroscopy

Background:

• Molecular photoelectron and Auger electron spectroscopy provide insights into electronic structure.
• Accurate theoretical models are crucial for interpreting complex spectral data.
• Previous models faced challenges in efficiently calculating continuum wave functions.

Purpose of the Study:

• To apply and validate the spherically averaged continuum model for molecular photoelectron and resonant Auger electron spectra.
• To assess the accuracy of different approximations for Auger transition matrix elements.
• To provide a reliable computational tool for spectral interpretation.

Main Methods:

• Solving the radial Schrödinger equation with a numerically efficient, spherically averaged molecular potential.
• Utilizing the spherically averaged continuum model to obtain continuum wave functions.
• Testing the one-center approximation against experimental data for CH4, O2, NO2, and pyrimidine.

Main Results:

• The model accurately estimates the shapes of photoelectron and autoionization spectra.
• It provides reasonable accuracy for total Auger decay rates.
• The one-center approximation shows good performance for the tested molecules.

Conclusions:

• The spherically averaged continuum model is a viable and accurate method for evaluating molecular electron spectra.
• This approach facilitates the interpretation of experimental photoelectron and Auger electron spectra.
• The model offers a computationally efficient pathway for theoretical spectroscopy.