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DOE OSTI · 2395988

Real-Space Pseudopotential Method for the Calculation of Third-Row Elements X-ray Photoelectron Spectroscopic Signatures

Liu, Liping·Xu, Qiang·dos Anjos Cunha, Leonardo·Xin, Hongliang·Head-Gordon, Martin·Qian, Jin
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Abstract

X-ray photoelectron spectroscopy (XPS) is a powerful characterization technique that unveils subtle chemical environment differences via core– electron binding energy (CEBE) analysis. We extend the development of realspace pseudopotential methods to calculating 1s, 2s, and 2p 3/2 CEBEs of third-row elements (S, P, and Si) within the framework of Kohn–Sham density-functional theory (KS-DFT). The new approach systematically prevents variational collapse and simplifies core-excited orbital selection within dense energy level distributions. However, careful error cancellation analysis is required to achieve accuracy comparable to all-electron methods and experiments. Combined with real-space KS-DFT implementation, this development enables large-scale simulations with both Dirichlet boundary conditions and periodic boundary conditions.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYBinding EnergyChemical CalculationsElementsMoleculesX-Ray Photoelectron Spectroscopy

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Liu, Liping, Xu, Qiang, dos Anjos Cunha, Leonardo, Xin, Hongliang, Head-Gordon, Martin, Qian, Jin. 2024-07-05. Real-Space Pseudopotential Method for the Calculation of Third-Row Elements X-ray Photoelectron Spectroscopic Signatures. https://doi.org/10.1021/acs.jctc.4c00535

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