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 calculations, we study the thermodynamic properties of α-Pu. To do this, we build on recent work in the literature by introducing a novel noncollinear magnetic ansatz for α-Pu's ground state. We show that the noncollinear ansatz improves the description of the experimental phonon density of states, heat capacity, and thermal expansion over previous results obtained with a collinear ansatz. Despite lacking a bond-equivalent picture of the bonding, these new results for α-Pu, along with recent results on δ-Pu, demonstrate the efficacy of noncollinear ansatzes for the description of plutonium.
| Original language | English |
|---|---|
| Article number | 156151 |
| Journal | Journal of Nuclear Materials |
| Volume | 617 |
| DOIs | |
| State | Published - Nov 2025 |
Funding
The authors would like to thank Per Söderlind for providing the heat capacity data for the collinear calculation as well as his advice and encouragement in pursuing this work. The authors would like to acknowledge the LDRD project number 20230042DR. This research used resources provided by the Los Alamos National Laboratory Institutional Computing Program, which is supported by the U.S. Department of Energy National Nuclear Security Administration under Contract No. 89233218CNA000001.