Department of Physics, National Technical University of Athens, Athens, Greece.
J Phys Condens Matter. 2012 Nov 7;24(44):442001. doi: 10.1088/0953-8984/24/44/442001. Epub 2012 Sep 14.
In the quest for the construction of silicene, the silicon analogue of graphene, recent experimental studies have identified a number of distinct ultrathin Si over-layer structures on a Ag(111) surface. Here we use first-principles calculations to probe associated atomic-scale mechanisms that can give rise to this rich behavior of Si wetting layers. We find that the interaction between the Si film and the Ag substrate, neither too strong nor too weak, combined with the possibility of buckling, allows for the incorporation of a number of excess Si adatoms in continuous overlayers with a honeycomb network topology. Depending on the Si coverage, we thus obtain a hierarchy of Si mono-atomic films, in agreement with experiments.
在构建硅烯（石墨烯的硅类似物）的过程中，最近的实验研究在 Ag(111)表面上确定了许多不同的超薄 Si 覆盖层结构。在这里，我们使用第一性原理计算来探究相关的原子尺度机制，这些机制可以导致 Si 润湿层的这种丰富行为。我们发现，Si 膜与 Ag 衬底之间的相互作用既不太强也不太弱，再加上可能发生的屈曲，允许在具有蜂窝状网络拓扑的连续覆盖层中掺入许多多余的 Si adatoms。因此，根据 Si 的覆盖率，我们得到了一系列 Si 单原子膜，与实验结果一致。
