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arXiv · 2403.11457

First-Principles Calculation of Hubbard U for Terbium Metal under High Pressure

Logan A. Burnett·Matthew P. Clay·Yogesh K. Vohra·Cheng-Chien Chen
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Abstract

Using density functional theory (DFT) and linear response approaches, we compute the on-site Hubbard interaction $U$ of elemental Terbium (Tb) metal in the pressure range $\sim 0-65$ GPa. The resulting first-principles $U$ values with experimental crystal structures enable us to examine the magnetic properties of Tb using a self-consistent DFT+U method. The lowest-energy magnetic states in our calculations for different high-pressure Tb phases -- including hcp, $\alpha$-Sm, and dhcp -- are found to be compatible with the corresponding magnetic ordering vectors reported in experiments. The result shows that the inclusion of Hubbard $U$ substantially improves the accuracy and efficiency in modeling correlated rare-earth materials. Our study also provides the necessary $U$ information for other quantum many-body techniques to study Tb under extreme pressure conditions.

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Logan A. Burnett, Matthew P. Clay, Yogesh K. Vohra, Cheng-Chien Chen. 2024-03-18. First-Principles Calculation of Hubbard U for Terbium Metal under High Pressure. https://doi.org/10.1088/1361-648x%2Fad6387

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