Abstract Using scanning tunneling microscopy and density functional theory calculations, atomic arrangement of surface reconstructions in Pb/Si(100) system was examined. Through accurate evaluation of Pb coverage, it was determined that 2 × 2 reconstruction contains 0.5 monolayer (ML) of Pb, c(8 × 4) - 0.75 ML of Pb, 2 × 1 - 1.5 ML of Pb, and c(4 × 4) - 1.875 (15/8) ML of Pb. It was revealed that the 2 × 2-Pb reconstruction can occur in two possible modifications, with buckled Pb dimers in the trenches between Si-dimer rows and with symmetric Pb dimers atop Si-dimer rows. The 2 × 2-Pb reconstruction of the latter type develops mainly on the Si(100)2 × 1 surface which contains relatively large density of structural defects. Known structural models of the c(8 × 4) and 2 × 1 reconstructions were tested and received the confirmation. A new model was proposed for the c(4 × 4) structure. The obtained data set is believed to constitute a solid base for the prospective studies of the phenomena occurring in the Pb/Si(100) system. In particular, the Pb-dense reconstructions, 2 × 1 and c(4 × 4), might be plausible candidates for detecting superconducting properties by analogy with the Pb-dense reconstructions on Si(111).

中文翻译：

---

Pb/Si(100) 系统中的表面重建：组成和原子排列

摘要 利用扫描隧道显微镜和密度泛函理论计算，研究了 Pb/Si(100) 系统表面重构的原子排列。通过对 Pb 覆盖率的准确评估，确定 2 × 2 重建包含 0.5 单层 (ML) Pb、c(8 × 4) - 0.75 ML Pb、2 × 1 - 1.5 ML Pb 和 c(4 × 4) - 1.875 (15/8) 毫升铅。结果表明，2×2-Pb 重建可以发生在两种可能的修改中，在 Si-二聚体行之间的沟槽中具有弯曲的 Pb 二聚体，在 Si-二聚体行的顶部具有对称的 Pb 二聚体。后一种类型的 2 × 2-Pb 重建主要发生在 Si(100)2 × 1 表面，该表面含有相对较大密度的结构缺陷。对 c(8 × 4) 和 2 × 1 重建的已知结构模型进行了测试并得到了确认。针对 c(4 × 4) 结构提出了一种新模型。所获得的数据集被认为构成了对 Pb/Si(100) 系统中发生的现象的前瞻性研究的坚实基础。特别是，2 × 1 和 c(4 × 4) 的 Pb 密集重建可能是通过类比 Si(111) 上的 Pb 密集重建来检测超导特性的合理候选者。