Abstract:
The electronic structure of the new superconductor PuCoIn$_5$ has been examined within the LDA+U+SO method taking into account both strong electron correlations and spin-orbit coupling between $5f$ electrons of an actinide metal. As compared to the characteristics of the known superconductor PuCoGa$_5$, Pu $5f$ states in PuCoIn$_5$ are more localized but with an intermediate type of coupling between $5f$ electrons with a strong prevalence of the $LS$ type. However, at a small volume corresponding to the volume of the unit cell of the PuCoGa$_5$ superconductor, the electronic and spectral characteristics of PuCoIn$_5$ are close to the corresponding parameters of PuCoGa$_5$. It has been shown that the occupancy of Co $3d$ states in PuCoIn$_5$ is close to the previously estimated limiting values providing the optimal doping regime in the electron subsystem of super-conductors of the Pu-115 series.