A noncollinear density functional theory ansatz for the phononic and thermodynamic properties of α-Pu

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 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. The noncollinear ansatz accurately recovers the experimental phonon density of states, heat capacity, and thermal expansion. These new results on α-Pu along with recent results on δ-Pu demonstrate the efficacy of noncollinear ansatzes for the description of plutonium.