
A density functional theory study on sizedependent structures, stabilities, and electronic properties of the bimetallic M_{n}Ag_{m} (M=Na, Li; n+m ≤ 7) clusters
Sun HaoRan, Kuang XiaoYu, Li YanFang, Shao Peng, Zhao YaRu
Chin. Phys. B, 2012, 21 (8):
083601.
DOI: 10.1088/16741056/21/8/083601
The equilibrium geometries, relative stabilities, and electronic properties of M_{n}Ag_{m }(M=Na, Li; n+m≤ 7) as well as pure Ag_{n}, Na_{n}, Li_{n } (n≤ 7) clusters are systematically investigated by means of density functional theory. The optimized geometries reveal that for 2≤ n ≤ 7, there are significant similarities in geometry among pure Ag_{n}, Na_{n}, and Li_{n} clusters, and the transitions from planar to threedimensional configurations occur at n=7, 7, and 6, respectively. In contrast, the first threedimensional (3D) structures are observed at n+m=5 for both Na_{n}Ag_{m} and Li_{n}Ag_{m} cluters. When n+m ≥ 5, a striking feature is that the trigonal bipyramid becomes the main subunit of Li_{n}Ag_{m}. Furthermore, dramatic oddeven alternative behaviours are obtained in the fragmentation energies, secondorder difference energies, highest occupied and lowest unoccupied molecular orbital energy gaps, and chemical hardness for both pure and doped clusters. The analytic results exhibit that clusters with even electronic configuration (2, 4, 6) possess weakest chemical reactivity and more enhanced stability.
