物理化学学报 >> 2007, Vol. 23 >> Issue (11): 1723-1727.doi: 10.3866/PKU.WHXB20071113

研究论文 上一篇    下一篇

Pdn(n=1-7)团簇及其与甲烷相互作用的密度泛函理论研究

姜勇; 储伟; 江成发; 王耀红   

  1. 四川大学化工学院, 成都 610065; 四川大学建筑与环境学院, 成都 610065
  • 收稿日期:2007-05-11 修回日期:2007-07-18 发布日期:2007-11-01
  • 通讯作者: 储伟 E-mail:chuwei.scu.cn@163.com

A DFT Study of Pdn(n=1-7) Clusters and Their Interactions with CH4 Molecule

JIANG Yong; CHU Wei; JIANG Cheng-Fa; WANG Yao-Hong   

  1. College of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China; College of Environment & Architecture, Sichuan University, Chengdu 610065, P. R. China
  • Received:2007-05-11 Revised:2007-07-18 Published:2007-11-01
  • Contact: CHU Wei E-mail:chuwei.scu.cn@163.com

摘要: 用密度泛函理论(DFT)的B3LYP方法, 对Pdn(n=1-7)团簇的几何结构、振动频率及其与甲烷分子间的相互作用进行了理论研究. 结果表明, 随着Pd原子数增多, 团簇结构对团簇大小的依赖性减弱, 结构参数向金属晶体趋近. 在Pdn(n=1-7)团簇上, 甲烷的表面吸附作用较弱. Pd2CH4中, 甲烷受到两个Pd原子的活化作用, 活化程度增强, 吸附能增大. 在PdnCH4 (n=1, 3-7)体系中, 甲烷的吸附能随着团簇模型的增大而减小, 趋近于其在金属晶面上的吸附能.

关键词: 甲烷, Pdn(n=1-7)团簇, 密度泛函理论, 吸附

Abstract: The geometric configurations, vibrational frequencies of Pdn(n=1-7) clusters and their interactions with a CH4 molecule were studied using the DFT/B3LYP method. Increasing the total number of palladium atoms made the cluster less size-dependent and structural parameters approach to the bulk solid. Methane adsorption on Pdn(n=1-7) clusters was very weak. Methane was activated by Pd2 cluseter, activation and adsorption energy were aggrandized. With increasing cluster size, the interaction of molecular-surface in PdnCH4 (n=1,3-7) clusters became weak, and the adsorption energy approached to that on the bulk metal.

Key words: Methane, Pdn(n=1-7) clusters, Density functional theory, Adsorption

MSC2000: 

  • O641