物理化学学报 >> 2010, Vol. 26 >> Issue (11): 3061-3066.doi: 10.3866/PKU.WHXB20101112

量子化学及计算化学 上一篇    下一篇

六核钽铑二元混合簇合物的几何和电子结构

曹飞1,2, 谭凯2, 林梦海2   

  1. 1. 九江学院化学化工学院,江西九江332005;
    2. 厦门大学化学化工学院化学系,福建厦门361005
  • 收稿日期:2010-06-13 修回日期:2010-08-06 发布日期:2010-10-29
  • 通讯作者: 曹飞 E-mail:jjyz2001@163.com
  • 基金资助:

    国家自然科学基金(20873107, 20373053)资助项目

Geometric and Electronic Structures of Hexanuclear Binary Ta/Rh Mixed Clusters

CAO Fei1,2, TAN Kai2, LIN Meng-Hai2   

  1. 1. College of Chemistry and Chemical Engineering, Jiujiang University, Jiujiang 332005, Jiangxi Province, P. R. China;
    2. Departmental of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian Province, P. R. China
  • Received:2010-06-13 Revised:2010-08-06 Published:2010-10-29
  • Contact: CAO Fei E-mail:jjyz2001@163.com
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20873107, 20373053).

摘要:

采用密度泛函理论对六核钽、铑八面体纯簇及其混合簇的几何结构和电子性质进行了研究. 计算结果表明:大部分钽铑混合簇稳定构型的对称性均较低, 为C1Cs点群, 只有[Ta2Rh4Cl4H8(CN)6]4-团簇的稳定构型对称性较高,为C2hC4v 点群;混合簇的最高占据分子轨道(HOMO)与最低未占据分子轨道(LUMO)能隙(△EH-L)均较小, 介于0.52-1.00 eV 之间; 混合簇的前线轨道主要由骨架金属原子的d 电子贡献, 随着Rh 原子替代Ta 原子个数的递增, Ta—Rh 键对混合簇稳定构型所起作用逐渐增加, Ta—Ta 键所起作用减小, 而Rh—Rh 键为非键或反键性质.

 

关键词: 密度泛函理论, 过渡金属团簇, 金属键, 钽,

Abstract:

Density functional theory (DFT) was employed to investigate the geometric and electronic properties of a series of hexanuclear binary Ta/Rh clusters. The results show that most of the stable structures of the Ta/Rh mixed clusters have low symmetry and belong to the C1 or Cs point groups while the [Ta2Rh4Cl4H8(CN)6]4- clusters are highly symmetric (C2h or C4v). The energy gaps (△EH-L) between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the mixed clusters are narrow and within 0.52-1.00 eV. A frontier orbital analysis of the mixed clusters clearly shows that the molecular orbitals are mainly composed of the d-orbitals of the skeleton metal atoms. When more rhodium atoms are substituted for tantalum atoms, the Ta—Rh bond has a greater influence on the stable structures of the mixed clusters and the influence of Ta—Ta bond decreases while the Rh—Rh bond has a non-bonding or anti-bonding nature.

 

Key words: Density functional theory, Transition-metal cluster, Metal bond, Tantalum, Rhodium

MSC2000: 

  • O641