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DOE OSTI · 3025397

Mott vs Kondo: Influence of various density functional based methods on the Ce isostructural phase transition mechanism

Abstract

The cerium iso-structural phase transition (γ–α) is dominated by f-electron localization changes that results in a magnetic ordering change and a volume collapse. Generally, these physics are difficult to capture with ab initio and first principles methods. However, previous works have shown various methods to be successful in predicting at least some of the physics of the γ to α phase transition. Therefore, here, we perform a broad survey of density functional based methods across three levels of theory and types of functions [GGA (generalized gradient approximation), MetaGGA, and hybrid functionals] and compare the results, focusing on hydrostatic compression across the phase boundary at zero kelvin. For the methods that best reproduce experimental results, we directly probe the predicted mechanisms and frame the results in the Mott/Kondo debate, assessing how the underlying methods and assumptions of different functionals can assess the physical drivers in the phase transition, providing insight into the governing processes of this unique phase transition.

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BibTeXRIS

Hamilton, Brenden William [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000245242201), Muñoz, Alexander Reed [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Jones, Travis Elliott Loyd [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000189217641), Nebgen, Benjamin Tyler [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000153103263). 2026-02-03. Mott vs Kondo: Influence of various density functional based methods on the Ce isostructural phase transition mechanism. https://doi.org/10.1063/5.0309770

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36 MATERIALS SCIENCE↗