Electronic structure and correlation effects in PuCoIn ₅ as compared to PuCoGa ₅

Since their discovery nearly a decade ago, plutonium-based superconductors have attracted considerable interest, which is now heightened by the latest discovery of superconductivity in PuCoIn ₅. In the framework of density functional theory (DFT) within the generalized gradient approximation (GGA) together with dynamical mean-field theory (DMFT), we present a comparative study of the electronic structure of superconducting PuCoIn ₅ with an expanded unit cell volume relative to its PuCoGa ₅ cousin. Overall, a similar GGA-based electronic structure, including the density of states, energy dispersion, and Fermi surface topology, was found for both compounds. The GGA Pu 5f band was narrower in PuCoIn ₅ than in PuCoGa ₅ due to the expanded lattice, resulting in an effective reduction of Kondo screening in the former system, as also shown by our DMFT calculations.