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

• 来源期刊: 中国物理B（英文版）
• 关键词: MnAgm (M=Na,Li) clusters density functional theory relative stability
• 年，卷（期）: 2012,（8）
• 页码范围: 202-210
• 页数: 9页
• 语种: 英文
• DOI: 10.1088/1674-1056/21/8/083601

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 the 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 clusters.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,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 an even electronic configuration (2,4,6) possess the weakest chemical reactivity and more enhanced stability.