Designing Pu intermetallics with first principle calculations

Due to experimental handling difficulties associated with the radioactive nature of elemental Pu, large phase spaces of Pu based intermetallic compounds remain largely unexplored. Yet, knowledge of the f-electron physics associated with transuranium elements requires further attention, as evidenced by the higher superconducting energy scales of PuCoGa₅ relative to non-Pu 1:1:5 complements [1]. Keeping in mind Pu experimental difficulties, we utilize density functional theory calculations and predict the stability of PuXN (X = transition metals; N = post-transition metals) compounds. Polycrystalline samples of PuNiSn and PuPtSn were arc melted and confirmed to form in the orthogonal TiNiSi-type structure [space group Pnma] and the hexagonal ZrNiAl-type structure [P62m], respectively. We report thermal and magnetic properties that are consistent with antiferromagnetic order at low temperatures. We compare these compounds with the previously reported PuPdSn [2] and comment on the nature of the 5f-states in these materials.

[1] Daghero, D., M. Tortello, G.A. Ummarino, J.-C. Griveau, E. Colineau, R. Eloirdi, A.B. Shick, J. Kolorenc, A.I. Lichtenstein, and R. Caciuffo. “Strong-Coupling d-Wave Superconductivity in PuCoGa5 Probed by Point-Contact Spectroscopy.” Nature Communications 3, no. 1 (April 17, 2012): 786. https://doi.org/10.1038/ncomms1785.

[2] Gofryk, K., J.-C. Griveau, E. Colineau, R. Jardin, J. Rebizant, F. Wastin, and R. Caciuffo. “Magnetic and Related Properties of PuPdSn.” Journal of Nuclear Materials 385, no. 1 (March 2009): 46–48. https://doi.org/10.1016/j.jnucmat.2008.09.049.