物理化学学报 >> 2009, Vol. 25 >> Issue (08): 1485-1489.doi: 10.3866/PKU.WHXB20090903

研究论文 上一篇    下一篇

一氧化碳共吸附法确定叔丁胺分子在Cu(111)表面的吸附位

陈毓敏, 邓珂, 裘晓辉, 王琛   

  1. 国家纳米科学中心, 北京 100190
  • 收稿日期:2009-06-16 修回日期:2009-06-29 发布日期:2009-07-16
  • 通讯作者: 裘晓辉, 王琛 E-mail:xhqiu@nanoctr.cn; wangch@nanoctr.cn

Determination of the Adsorption Sites of tert-Butylamine Molecules on a Cu(111) Surface with a Co-Adsorbed CO Monolayer

CHEN Yu-Min, DENG Ke, QIU Xiao-Hui, WANG Chen   

  1. National Center for Nanoscience and Technology, China, Beijing 100190, P. R. China
  • Received:2009-06-16 Revised:2009-06-29 Published:2009-07-16
  • Contact: QIU Xiao-Hui, WANG Chen E-mail:xhqiu@nanoctr.cn; wangch@nanoctr.cn

摘要:

采用扫描隧道显微镜(STM)和密度泛函理论(DFT)研究了78 K时单个叔丁胺分子在Cu(111)表面的吸附位. 我们提出以共吸附的一氧化碳√3 ×√3 超结构为基底铜原子的标识方法, 确定了低覆盖度的叔丁胺分子在Cu(111)表面的吸附位为顶位. 而采用单个一氧化碳分子标识基底铜原子的位置, 同样得出了叔丁胺分子的吸附位为顶位. 此外, 还采用DFT计算叔丁胺分子在Cu(111)表面的优势吸附构型. 理论计算结果表明顶位吸附构型为能量最稳定的构型, 与实验结果相吻合.

关键词: 扫描隧道显微镜, 吸附位, 单分子, 共吸附, 密度泛函理论

Abstract:

Scanning tunneling microscopy (STM) and density functional theory (DFT) were used to investigate the adsorption sites of separable tert-butylamine (t-BA) molecules on a Cu(111) surface at 78 K. We developed a method that uses CO molecules on a co-adsorbed √3 ×√3 superstructure as markers for copper atoms on the surface lattice. This method revealed an on-top adsorption for t-BA on the Cu(111) surface. At low coverage, t-BA molecules preferentially adsorbed at the top sites of the Cu(111) surface and this was confirmed using a single CO molecule as a marker for a copper atom. DFT calculations were performed to study the most stable adsorption configuration of t-BA on the terrace of the Cu(111) surface at 78 K. Calculation results indicate that the top site is the most energetically preferred adsorption site for a single t-BA molecule on the terrace, which agrees well with the experimental results.

Key words: Scanning tunneling microscopy, Adsorption site, Single molecule, Co-adsorption, Density functional theory

MSC2000: 

  • O641