Insight into the Relationship Between Structural and Electronic Properties of Bimetallic RhnPt55−n (n = 0–55) Clusters with Cuboctahedral Structure: DFT Approaches

Abstract

The relationships of structural, magnetic, and electronic properties of bimetallic RhnPt55−n (n = 0–55) clusters with cuboctahedral structure as varying compositions have been investigated using density functional theory calculations. Our results indicate that the Pt atoms tend to segregate to the surface, especially locating at the vertex site, while the Rh atoms prefer to the core site. In random alloy structures, Rh27Pt28 cluster has the lowest excess energy of −2.49 eV. However, the ordered core–shell structure, Rh13@Pt42, has much lower excess energy of −5.16 eV. In addition, our calculations have indicated that the total magnetic moments of bimetallic RhnPt55−n clusters are weakened except the Rh27Pt28 with respect to Rh55 cluster, while the average local magnetic moments of Rh and Pt atoms are mainly enhanced compared with their pure phases. As for the electronic properties, the d -band center (|e d * |) of Rh and Pt as well as the s-, p-, d-partial density of states (s-, p-, d-PDOS) reveal the relationship between the electronic properties and structural stabilities. Meanwhile, the d-PDOS has interpreted the varying magnetic moments. The stable bimetallic RhnPt55−n (n = 0–55) clusters with cuboctahedral structure as varying compositions are investigated by density functional theory calculations.