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arXiv · 2405.14816

A noncollinear density functional theory ansatz for the phononic and thermodynamic properties of $\alpha$-Pu

Alexander R. Muñoz·W. Adam Phelan·Matthew S. Cook·Greta L. Chappell·Paul H. Tobash·David C. Arellano·Derek V. Prada·Travis E. Jones·Sven P. Rudin
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Abstract

Plutonium's phase diagram is host to complex structures and interactions that make the description of its ground state properties elusive. Using all-electron density functional theory, we study the thermodynamic properties of $\alpha$-Pu. To do this, we build on recent work in the literature by introducing a novel noncollinear magnetic ansatz for $\alpha$-Pu's ground state. The noncollinear ansatz accurately recovers the experimental phonon density of states, heat capacity, and thermal expansion. These new results on $\alpha$-Pu along with recent results on $\delta$-Pu demonstrate the efficacy of noncollinear ansatzes for the description of plutonium.

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Alexander R. Muñoz, W. Adam Phelan, Matthew S. Cook, Greta L. Chappell, Paul H. Tobash, David C. Arellano, Derek V. Prada, Travis E. Jones, Sven P. Rudin. 2024-05-23. A noncollinear density functional theory ansatz for the phononic and thermodynamic properties of $\alpha$-Pu. https://arxiv.org/abs/2405.14816

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