Electronic and Structural Properties of M@Si12 and M@Si12H12 Clusters, M = Ni, Zn.

The electronic and structural characteristics of M@Si12 and M@Si12H12 clusters are studied in parallel for both Ni and Zn with the help of partial and total densities of States (DOS) and Crystal-Orbital-Overlap-Population (COOP) diagrams. These results are compared with those for empty hydrogenated cages. In this case the emphasis is placed on the role of hydrogen in the stabilization of the cages as an alternative to metal (M) atom encapsulation, as was suggested recently (A. D. Zdetsis Phys. Rev. B 75, 085409, and Phys. Rev. B 76, 075402, 2007). The present results support this idea. Furthermore, it is verified that surface hydrogen considerably weakens the contribution of the metal atom to the overall binding, which is dominated by the silicon-hydrogen interaction. [ABSTRACT FROM AUTHOR]