用改进嵌入原子法计算Cu晶体的表面能

Calculation of surface energy of Cu crystal with modified embedded-atom method

用改进嵌入原子法 (MEAM)计算了Cu晶体 12个晶面的表面能 .结果表明 ,密排面 (111)的表面能最小 .其他晶面的表面能随其晶面与 (111)晶面夹角的增加而增加 ,据此可以粗略地估计各晶面表面能的相对大小 .给出的几何结构因子的确定方法及结果可以直接用于计算其他面心立方晶体的表面能及其他特性 .在Cu ,Ag等面心立方薄膜中出现 (111)择优取向或织构的机理是表面能的最小化 .

The surface energies on 12 different planes of Cu crystal have been calculated with modified embedded-atom method. The results show that the lowest surface energy, as predicted, corresponds to the close-packed plane (111) of face-centered cubic (FCC) structure. The surface energies on other planes show a tendency to increase with increasing angle between the planes and (111) plane. So the relative values in surface energy for other planes could be estimated by their geometric relationship. The geometric structure factors and the methods applied to determine them could be used directly for surface energy and other property calculations in the materials with FCC structure. The (111) texture observed extensively in Cu, Ag and other FCC films results from the surface energy minimization.