Character of $5f$ states in the Pu-Am system from magnetic susceptibility, electrical resistivity, and photoelectron spectroscopy measurements
Résumé
Alloying Pu with Am stabilizes the fcc structure of $\delta$−Pu for all temperatures and expands the lattice. $\delta$-Pu is assumed close to the borderline of $5f$ localization. It is a nonmagnetic strongly correlated system, which should be sensitive to doping or lattice expansion. However, magnetic susceptibility, electrical resistivity, and photoelectron spectroscopy studies performed for the Pu-rich part (from 5 to 43 % Am) of the Pu-Am phase diagram indicate that the character of the $5f$ states does not vary with the Am doping. These findings are discussed within the present debate about the electronic structure of plutonium.