A parallel study of Ni@Si-12 and Cu@Si-12 nanoclusters

作者：Zdetsis A D^*; Koukaras E N; Garoufalis C S

来源：Journal of Mathematical Chemistry, 2009, 46(3): 971-980.

DOI：10.1007/s10910-009-9549-x

• Metal encapsulated clusters
• Nanocluster
• Silicon
• Transition metal
• Ab initio calculations

The Ni@Si-12 and Cu@Si-12 clusters are studied in parallel within the framework of the density functional theory using the hybrid functional of Becke-Lee, Parr and Yang (B3LYP), emphasizing the differences and similarities in structural and electronic properties. The dominant structures for both clusters are a distorted hexagonal structure of C-s symmetry and a distorted octahedral structure of D-2d. For Ni@Si-12 the two structures are practically isonergetic whereas for Cu@Si-12 the energy difference of the D-2d structure from the lowest C-s structure of hexagonal origin is about 0.7 eV, at the B3LYP/TZVP level of theory. Contrary to Cu@Si-12 for which the well known Frank-Kasper (FK) structure of C-5v symmetry is a real local minimum of the energy hyper-surface (although higher by more than 1.6 eV from the global minimum), for Ni@Si-12 the FK structure is dynamically unstable. The HOMO-LUMO gaps, the binding energies per atom and the embedding energies for Cu@Si-12 clusters are smaller by 0.5, 0.1 and 1.1 eV, respectively compared to the Ni@Si-12 clusters. This is attributed to different type of bonding in the two clusters.

• 出版日期2009-10