Density-functional study of Zr-based actinide alloys: 2. U-Pu-Zr system

Density-functional theory, previously used to describe phase equilibria in the U-Zr alloys [A. Landa, P. Söderlind, P.E.A. Turchi, L. Vitos, A. Ruban, J. Nucl. Mater. 385 (2009) 68], is applied to study ground-state properties of the bcc U-Pu-Zr solid solutions. Calculated heats of formation of the Pu-U and Pu-Zr alloys are in a good agreement with CALPHAD assessments. We found that account for spin-orbit coupling is important for successful description of Pu-containing alloys.