Abstract An extended elastic eigenvector approach had earlier been developed to interpret ab-initio calculations of adatom interactions. It shows oscillating interactions as well as trio- and quarto (multisite) terms within clusters. It is now applied to the interaction of Fe adatoms on Cu(111). The extended approach differs from previous calculations by using a sharp cutoff - generating oscillating interactions - and by taking into account interacting dimers - generating strong anisotropies and multisite terms. Additional weak anisotropy stems from the substrate and from the surface Brillouin zone shape. This approach has 3 free parameters which have been fitted to first principles interactions of Fe adatoms on Cu(111). Elastic adatom pair interactions and dimer-dimer interactions at mesoscale separations show a reasonable good fit to the first principles interactions. At smaller separations elastic interaction values remain questionable. To enable a comparison with future first principle calculations also dimer-monomer interactions are shown. Some conclusions on initial adatom formation and diffusion are proposed and open questions are formulated.

中文翻译：

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Fe吸附原子在中尺度Cu(111)上的弹性相互作用

摘要 较早开发了一种扩展的弹性特征向量方法来解释吸附原子相互作用的从头计算。它显示了集群内的振荡相互作用以及三重奏和四重奏（多站点）项。它现在应用于 Fe 吸附原子在 Cu(111) 上的相互作用。扩展方法与之前的计算不同，它使用了一个尖锐的截止点——产生振荡相互作用——并考虑到相互作用的二聚体——产生强各向异性和多位点项。额外的弱各向异性源于衬底和表面布里渊区形状。该方法具有 3 个自由参数，这些参数已拟合 Fe 吸附原子在 Cu(111) 上的第一原理相互作用。中尺度分离处的弹性吸附原子对相互作用和二聚体-二聚体相互作用显示出与第一原理相互作用的合理良好拟合。在较小的间距下，弹性相互作用值仍然值得怀疑。为了能够与未来的第一原理计算进行比较，还显示了二聚体-单体相互作用。提出了一些关于初始吸附原子形成和扩散的结论，并提出了开放性问题。