O2分子在Al(110)表面选择吸附性的对比研究

采用密度泛函理论中广义梯度近似(GGA)计算方法对比分析了 O2分子在 Al(110)面3个不同吸附位(顶位、桥位和穴位)的吸附性质，通过吸附能的比较，桥位的吸附能高于顶位和穴位，是最佳的吸附位。吸附质的态密度、吸附物 O2分子轨道电荷分布的变化以及金属表面原子轨道电荷分布的变化揭示了吸附过程中电荷的转移趋势。计算结果表明，通过分析吸附质的原子轨道电荷分布和电子态密度，发现 O2在 Al(110)表面吸附的过程中，主要是 O 原子的2P 轨道和 Al 的3S 轨道的电子相互作用，并展示出较强的化学吸附。

Comparative Study on the Selective Adsorption of O2 on Al(110)Surface

The adsorptive characters of O2 on Al (1 10)surface at three different sits (top,bridge and hollow) were investigated by using the generalized gradient approximation (GGA)based on density functional theory (DFT). By comparing the adsorption energies,it is able to deduce that the bridge site is the most favored site because its ad-sorption energy is larger than that at top and hollow site.The transfer trend of the charge in the progress of the ad-sorption is revealed by the density of states of adsorbate,orbital charge population change of O2 molecule and atomic orbital charge population change of metal surface.The conclusion is made that the main interaction in the process of O2 adsorption on Al (1 10)surface come from the 2P orbit of oxygen atom and 3S orbit of aluminum by analyzing the atomic orbital charge population and the electronic density of states of adsorbate,and there is a strong chemical ad-sorption between them.