清洁Nb(100)面的结构

The Structure of Clean Nb(100)Surface

采用低能电子衍射(LEED)动力学计算法,计算了Nb(100)面的各种弛豫结构的Ⅰ—Ⅴ曲线,使之与实验曲线拟合,用R 因子对这些可能的结构进行搜寻和分析.结果表明清洁Nb(100)面最顶层层间距为1.46(?),与体内相比向内收缩了11%,次层层间距为1.72(?),向外膨胀了5%,与清洁的Ta(100)面的结构相似.

A dynamical LEED calculation is applied to clean Nb(100)surface under study.The Ⅰ-Ⅴ curves of all possible relaxation structures are calculated and compared with the experimental results.The best structure is chosen with R-factor analysis.The calculated result claims a surface model with the top interlayer spacing of 1.46 (?) which is contracted by 11% with respect to the bulk value,while the second interlayer spacing is 1.72(?) which is expanded by about 5%.This model is very similar to that of clean Ta(100) surfsce.