On the structural, energetic, and magnetic properties of M@Pd (M = Co, Ni, and Cu) core-shell nanoclusters and their comparison with pure Pd nanoclusters

Abstract Electronic structure computations of pure Pd and Pd-based core–shell clusters were studied employing auxiliary density functional theory (ADFT). For this investigation icosahedral clusters with 13 and 55 atoms and octahedral clusters with 19 and 44 atoms were employed to analyze the change in the properties of the Pd and M@Pd core–shell clusters. All properties calculated for the M@Pd clusters are directly compared with the ones of pure palladium clusters. Spin multiplicities, spin magnetic moments, spin densities, binding energies per atom, segregation energies, and average bond lengths were calculated to understand their changes when varying the size, composition and shape of the M@Pd (M = Co, Ni, and Cu) core–shell clusters. The M1@Pd12 and M1@Pd18 (M = Co and Cu) clusters exhibit changes in the spin multiplicity and spin magnetic moment with respect to the Pd13 and Pd19 clusters, respectively, whereas the Ni1@Pd12 and Ni1@Pd18 clusters maintain the same properties as their pure Pd counterparts. The spin multiplicities and spin magnetic moments of the M6@Pd38 and M13@Pd42 (M = Co, Ni, and Cu) clusters greatly differ from their pure Pd counterparts. This study reveals that the Pd-Pd bond lengths are shorter in the M@Pd core–shell clusters compared to the ones of pure Pd clusters. This work demonstrates that the binding energy per atom of the M@Pd core–shell clusters is greater than the binding energy per atom of the pure Pd clusters. The calculated segregation energies indicate that 3d atoms prefer to be in the center of core–shell systems.