中国物理B ›› 2009, Vol. 18 ›› Issue (6): 2264-2270.doi: 10.1088/1674-1056/18/6/026

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Appearance of metallic features in small tungsten clusters

罗有华1, 雷雪玲2, 王先明2, 祝恒江2   

  1. (1)Department of Physics, East China University of Science and Technology, Shanghai 200237, China; (2)School of Maths-Physics and Information Sciences, Xinjiang Normal University, Urumqi 830054, China
  • 收稿日期:2008-08-01 修回日期:2008-11-17 出版日期:2009-06-20 发布日期:2009-06-20
  • 基金资助:
    Project supported by the Excellent Young Teachers' Foundation of Xinjiang Normal University (Grant No XJNU0730) and the Prior Developing Subject' Foundation of Xinjiang Normal University.

Appearance of metallic features in small tungsten clusters

Lei Xue-Ling(雷雪玲)a), Wang Xian-Ming(王先明)a), Zhu Heng-Jiang(祝恒江)a)†, and Luo You-Hua(罗有华)b)   

  1. a School of Maths-Physics and Information Sciences, Xinjiang Normal University, Urumqi 830054, China; b Department of Physics, East China University of Science and Technology, Shanghai 200237, China
  • Received:2008-08-01 Revised:2008-11-17 Online:2009-06-20 Published:2009-06-20
  • Supported by:
    Project supported by the Excellent Young Teachers' Foundation of Xinjiang Normal University (Grant No XJNU0730) and the Prior Developing Subject' Foundation of Xinjiang Normal University.

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摘要： The structures and properties of Wn (n=2--14) clusters were studied by using the density functional theory (DFT) at LSDA level. The most stable structures of Wn (n=2--14) clusters with global minimum were determined. The average binding energy (Eb), the first and second difference of total energy (\itδ E, \itδ2E), the vertical detachment energy (VDE), and the HOMO-LUMO gap versus the size were also discussed. The abrupt decrease of VDE and HOMO-LUMO gap at size n=8 and 10 implied that tungsten clusters of W8 and W10 appeared to have metallic features. These changes were also accompanied by the delocalization of electron charge density and the strong hybridization between 5d and 6s orbits in W8 and W_10 clusters. Our results are in good agreement with the available experimental data.

关键词: Wn clusters, density functional theory, lowest-energy structures, metallic features

Abstract: The structures and properties of $W_{n}$ ($n=2$--14) clusters were studied by using the density functional theory (DFT) at LSDA level. The most stable structures of $W_{n}$ ($n=2$--14) clusters with global minimum were  determined. The average binding energy ($E_{b})$, the first and second difference of total energy (${\it\Delta} E$, ${\it\Delta}_{2}E)$, the vertical detachment energy ({VDE}), and the HOMO-LUMO gap versus the size were also  discussed. The abrupt decrease of {VDE} and HOMO-LUMO gap at size $n=8$ and 10 implied that tungsten clusters of $W_{8}$ and $W_{10}$ appeared to have metallic features. These changes were also accompanied by the delocalization of electron charge density and the strong hybridization between $5d$ and $6s$ orbits in $W_{8}$ and $W_{10}$ clusters. Our results are in good agreement with the available experimental data.

Key words: Wn clusters, density functional theory, lowest-energy structures, metallic features

中图分类号:  (Electronic structure of nanoscale materials and related systems)

  • 73.22.-f
71.15.Mb (Density functional theory, local density approximation, gradient and other corrections) 71.15.Nc (Total energy and cohesive energy calculations) 71.20.Be (Transition metals and alloys)