CO在Ag(100)表面吸附行为的理论研究  

The theoretical study of CO adsorption on Ag( 100) surface

作　　者：刘新[1] 孟长功[1] 刘长厚[1] 

机构地区：[1]大连理工大学化学系,辽宁大连116024

出　　处：《计算机与应用化学》2005年第10期879-882,共4页Computers and Applied Chemistry

基　　金：国家自然科学基金资助项目(20273012)

摘　　要：应用离散变分Xα方法,对CO分子在Ag(100)表面的吸附过程进行了理论研究,计算了CO分子以垂直方式在三种不同吸附位置吸附时CO分子和Ag(100)表面原子间的键级和电荷分布。结果表明:在吸附过程中,CO分子以顶位吸附为优, 有效吸附距离为170±3 pm,在吸附过程中CO分子只与最近邻的一个表面银原子有相互作用,而其它表面原子及体相原子的电子结构没有变化。Mulliken集居数及局域态密度分析表明,吸附过程中银原子与CO之间的相互作用是表面Ag原子的杂化轨道电子进入CO中空的反键轨道(M→C)和CO上面(主要是C上)未成键电子进入到表面Ag原子空的杂化轨道(C→M) 的共同结果。The discrete variational Xα method （DVXα） within the framework of density function theory is applied to study CO molecule adsorption process on Ag（100） surface. The bond order and charge distribution between Ag atom and CO molecule for 3 possible adsorption sites are calculated. It is found that adsorption on top site is more preferred than the others and the effective adsorption distance is 170 ± 3 pm. CO molecule only interacts with nearest surface Ag atom during the adsorption. The electronic structure of the other surface atoms and bulk atoms are not altered. Mulliken population and partial density of state analysis show that the interaction between Ag atom and CO molecule is the over all effect of donation of unbonded electrons from C in CO to surface Ag atoms and back donation of hybrid electrons from surface Ag atoms to CO antibonding orbital.

关 键 词：表面吸附 一氧化碳 离散变分Xα方法 

分 类 号：O614[理学—无机化学]