论文部分内容阅读
根据计算机编程构造出了存在和不存在表面偏析的无序二元合金NixCu1 -x(x =0 4 )的原子集团模型 ,然后按覆盖度θ=0 5 ,构造出了CO表面吸附的模型 ,应用Recursion方法计算了CO在NixCu1 -x(存在偏析和不存在偏析时 )合金表面不同位置 (顶位和芯位 )吸附的电子结构 .由此得出 :1 )CO在顶位吸附时较稳定 ;2 )CO吸附使合金表面态密度峰降低 ,带宽加宽 ,使d轨道的局域性变弱 ;3)CO的吸附抑制了Cu在表面富集 ,从电子层次上解释了CO吸附于NixCu1 -x对合金表面偏析的影响机理
According to computer programming, the atomic group model of disordered binary alloy NixCu1-x (x = 0 4) with and without surface segregation was constructed, and then the model of CO surface adsorption was constructed according to the coverage θ = 0 5. The electronic structure of CO adsorbed on the surface of NixCu1-x (with or without segregation) was calculated by Recursion method, and the results showed that: 1) CO was more stable at the top adsorption ; 2) the adsorption of CO reduced the surface state density peak and broadened the bandwidth of the surface of the alloy, which made the localization of the d orbital weaken; 3) The adsorption of CO inhibited the enrichment of Cu on the surface and explained the adsorption of CO on NixCu1 Effect of -x on segregation of alloy surface