催化学报 ›› 2008, Vol. 29 ›› Issue (1): 75-80.

• 研究论文 • 上一篇    下一篇

Rh(111)表面上CO和O共吸附的密度泛函理论计算研究

杨明媚1,2,包信和1,李微雪1   

  1. 1 中国科学院大连化学物理研究所催化基础国家重点实验室, 辽宁大连 116023; 2 中国科学院研究生院, 北京 100049
  • 收稿日期:2008-01-25 出版日期:2008-01-25 发布日期:2011-12-25

A Density Functional Theory Study on Co-adsorption of CO and O on Rh(111) Surface

YANG Mingmei1,2, BAO Xinhe1, LI Weixue1*   

  1. 1 State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, The Chinese Academy of Sciences, Dalian 116023, Liaoning, China; 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2008-01-25 Online:2008-01-25 Published:2011-12-25

摘要: 采用密度泛函理论对Rh(111)表面上CO和O的吸附和共吸附进行了系统的研究,计算了三类不同的共吸附结构. 从吸附能和化学位移的角度,通过与已有实验结果对比,推断出可能存在的吸附构型. CO和O之间存在较大的排斥作用,在表面上竞争吸附. 电子结构分析发现,这种排斥作用来源于CO和O之间与Rh的d轨道成键的竞争. 用密度泛函理论计算的化学位移与实验测量结果一致,说明化学位移的理论计算能辅助对表面结构的预测.

关键词: 密度泛函理论, 一氧化碳, 氧, 吸附, 化学位移

Abstract: CO and O adsorption and co-adsorption on Rh(111) surfaces were studied by density functional theory calculations. Three types of co-adsorption systems, (2×2)-(CO+O), (2×2)-(2CO+O), and (2×2)-(CO+2O), were considered from energy, geometry, work function, and chemical shift points of view. The interactions between CO and O are repulsive, which is explained in terms of bonding competition. The calculated chemical shift of CO and O agrees well with experimental studies, which convince that it is a powerful method to predict the adsorption from theoretical chemical shifts.

Key words: density functional theory, carbon monoxide, oxygen, adsorption, chemical shift