中国物理B ›› 2012, Vol. 21 ›› Issue (8): 83601-083601.doi: 10.1088/1674-1056/21/8/083601

• ATOMIC AND MOLECULAR PHYSICS • 上一篇    下一篇

A density functional theory study on size-dependent structures, stabilities, and electronic properties of the bimetallic MnAgm (M=Na, Li; n+m ≤ 7) clusters

孙浩然, 邝小渝, 李艳芳, 邵鹏, 赵亚儒   

  1. Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
  • 收稿日期:2011-10-24 修回日期:2011-11-16 出版日期:2012-07-01 发布日期:2012-07-01
  • 基金资助:
    Project supported by the Doctoral Education Fund of the Education Ministry of Chain (Grant No.'20100181110086) and the National Natural Science Foundation of China (Grant Nos. 11104190 and 10974138).

A density functional theory study on size-dependent structures, stabilities, and electronic properties of the bimetallic MnAgm (M=Na, Li; n+m ≤ 7) clusters

Sun Hao-Ran (孙浩然), Kuang Xiao-Yu (邝小渝), Li Yan-Fang (李艳芳), Shao Peng (邵鹏), Zhao Ya-Ru (赵亚儒 )   

  1. Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
  • Received:2011-10-24 Revised:2011-11-16 Online:2012-07-01 Published:2012-07-01
  • Contact: Kuang Xiao-Yu E-mail:scu??kuang@163.com
  • Supported by:
    Project supported by the Doctoral Education Fund of the Education Ministry of Chain (Grant No.'20100181110086) and the National Natural Science Foundation of China (Grant Nos. 11104190 and 10974138).

摘要: The equilibrium geometries, relative stabilities, and electronic properties of MnAgm (M=Na, Li; n+m≤ 7) as well as pure Agn, Nan, Lin (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 Agn, Nan, and Lin clusters, and the transitions from planar to three-dimensional configurations occur at n=7, 7, and 6, respectively. In contrast, the first three-dimensional (3D) structures are observed at n+m=5 for both NanAgm and LinAgm cluters. When n+m ≥ 5, a striking feature is that the trigonal bipyramid becomes the main subunit of LinAgm. Furthermore, dramatic odd-even alternative behaviours are obtained in the fragmentation energies, second-order 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.

关键词: MnAgm (M=Na, Li) clusters, density functional theory, relative stability

Abstract: The equilibrium geometries, relative stabilities, and electronic properties of MnAgm (M=Na, Li; n+m≤ 7) as well as pure Agn, Nan, Lin (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 Agn, Nan, and Lin clusters, and the transitions from planar to three-dimensional configurations occur at n=7, 7, and 6, respectively. In contrast, the first three-dimensional (3D) structures are observed at n+m=5 for both NanAgm and LinAgm cluters. When n+m ≥ 5, a striking feature is that the trigonal bipyramid becomes the main subunit of LinAgm. Furthermore, dramatic odd-even alternative behaviours are obtained in the fragmentation energies, second-order 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.

Key words: MnAgm (M=Na,Li) clusters, density functional theory, relative stability

中图分类号:  (Configuration (bonds, dimensions))

  • 36.20.Hb
36.40.-c (Atomic and molecular clusters) 36.40.Qv (Stability and fragmentation of clusters)