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High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
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The Coupled-Resonances Asymmetric Lineshape for Photoemission Spectra
Alberto Herrera-Gomez1, Dulce Maria Guzman-Bucio1, Dagoberto Cabrera-German2
1CINVESTAV-Unidad Queretaro, Libramiento Norponiente 2000, Fracc. Real de Juriquilla, Queretaro 76230, Mexico.
The Journal of Physical Chemistry. C, Nanomaterials and Interfaces
|December 4, 2025
Summary
A new Coupled-Resonances (CR) line shape model accurately analyzes asymmetric peaks in photoelectron spectra, offering a robust alternative to the Doniach-Šunjić model for diverse materials.
Area of Science:
- Spectroscopy
- Materials Science
- Computational Chemistry
Background:
- The Doniach-Šunjić (D&S) model is widely used for asymmetric peaks in photoelectron spectra but has limitations.
- Existing models often struggle with accuracy beyond their intended scope, particularly for non-metallic materials.
- A need exists for a more versatile and accurate line shape model in photoemission spectroscopy.
Purpose of the Study:
- Introduce the Coupled-Resonances (CR) line shape model.
- Provide a theoretically robust method for analyzing asymmetric peaks in photoelectron spectra.
- Offer a superior alternative to the D&S model for a broader range of materials.
Main Methods:
- Developed the CR line shape model, incorporating an interference term to capture peak asymmetry.
- Implemented the CR model in the AAnalyzer software for practical application.
- Validated the CR model against experimental data, comparing CR Type-II and Type-III fits.
Main Results:
- The CR line shape accurately models asymmetric peaks in photoelectron spectra.
- CR model provides superior fits compared to the D&S model for various materials.
- Interference terms are crucial for accurately describing multiplet lineshapes with multiple resonances.
Conclusions:
- The CR line shape model is a significant advancement for analyzing photoemission spectroscopy data.
- The CR model offers greater accuracy and versatility than the D&S model.
- This new model is broadly applicable across metals and other materials, enhancing chemical composition analysis.
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