化学学报 ›› 2009, Vol. 67 ›› Issue (14): 1539-1546. 上一篇    下一篇

研究论文

金镍二元团簇结构和电子性质的理论研究

唐典勇* 金 诚 邹 婷 黄雪娜

  

  1. (乐山师范学院化学与生命科学学院 乐山 614000)

  • 投稿日期:2008-11-28 修回日期:2009-03-05 发布日期:2009-07-28
  • 通讯作者: 唐典勇

Theoretical Study on Structural and Electronic Properties of Small Gold-Nickel Binary Clusters

Tang, Dianyong* Jin, Cheng Zou, Ting Huang, Xuena

  

  1. (College of Chemistry and Life Science, Leshan Teacher’s College, Leshan 614000)
  • Received:2008-11-28 Revised:2009-03-05 Published:2009-07-28
  • Contact: TANG Dian-Yong

在UBP86/LANL2DZ和UBP86/def2-TZVP水平下详细研究了AumNin (m+n≤6)团簇的几何结构和电子性质. 详细地分析了团簇的结构特征, 平均结合能, 垂直电离势, 垂直电子亲和能, 电荷转移以及成键特征. 所有混合团簇中, 镍原子趋于聚集到一起, 形成最多Ni—Ni键, 金原子分布在镍原子聚集体周围以形成最多Au—Ni键. Ni原子较少团簇的电子性质与纯金团簇类似, 呈现一定奇偶振荡. 混合团簇中存在镍到金原子间的电荷转移. Ni原子较少团簇中, 自旋电子主要定域在Ni原子上, Ni原子较多团簇中, Au原子明显受到自旋极化. 混合团簇的分波态密度表明, AuNi混合团簇对小分子的反应活性要高于纯金团簇.

关键词: 金镍混合团簇, 垂直电离能, 垂直电子亲和能, 态密度(DOS), 密度泛函理论

The structural and electronic properties of small AumNin (m+n≤6) clusters have been studied at the UBP86/LANL2DZ and UBP86/def2-TZVP levels, respectively. Structural features, binding energies, vertical ionization potentials, vertical electron affinity, charge transfers, and binding characters were evaluated for each Au—Ni binary cluster. In all of the Au—Ni binary clusters, the nickel atoms are brought together, yielding the most Ni—Ni bonds, and the gold atoms are located around a Ni core with the most Au—Ni bonds. The vertical ionization potentials, vertical electron affinity, and Fermi level of the Au-rich clusters are similar to the pure gold clusters, demonstrating an odd-even oscillation. A very large electronic charge transfer from Ni to Au was found in the binary clusters. The spin density is located on Ni atoms in the Au-rich clusters, while the gold atoms are spin-polarized in the Ni-rich clusters. The partial density of state of the Au—Ni binary clusters makes it clear that the reactivity of the Au—Ni binary clusters toward the small molecule is higher than that of the pure gold clusters.

Key words: gold-nickel cluster, vertical ionization potential, vertical electron affinity, density of state (DOS), density functional theory