Accurate X-Ray Spectral Predictions: An Advanced Self-Consistent-Field Approach Inspired by Many-Body Perturbation Theory

Published

March 2, 2017

Author(s)

Yufeng Liang, John Vinson, Chaitanya D. Pemmaraju, Walter Drisdell, Eric L. Shirley, David Prendergast

Abstract

The self-consistent-field method and the many-body approach are two cornerstones for obtaining electronic excitations from first- principles. Using the two distinct theories, we study the O 1s core excitations that have become increasingly important for characterization of transition metal oxides and development of theory of strong correlations. Interestingly, we find that the self- consistent- field core-hole approach fails systematically in predicting the pre-peak feature for chosen oxides, despite its success in weakly correlated system, whereas the Bethe-Salpeter equation predicts much better lineshapes. We propose a simply model to fully rationalize the discrepancies of the two theories in terms of many-electron response and attribute the failure of core-hole approach to the "orthogonality catastrophe." The model points to the importance of dynamical effects and leads to a general discussion of the validity of the two approaches for a given system.

Citation

Physical Review Letters

Volume

118

Pub Type

Journals

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DOI Link

Citation

Liang, Y. , Vinson, J. , Pemmaraju, C. , Drisdell, W. , Shirley, E. and Prendergast, D. (2017), Accurate X-Ray Spectral Predictions: An Advanced Self-Consistent-Field Approach Inspired by Many-Body Perturbation Theory, Physical Review Letters, [online], https://doi.org/10.1103/PhysRevLett.118.096402 (Accessed December 12, 2024)