School of Mathematical and Physical Sciences, The University of Newcastle, Callaghan 2308, Australia.
J Chem Phys. 2010 Jul 7;133(1):014703. doi: 10.1063/1.3456736.
The adsorption of isolated H atoms on the Ge(001) surface is studied using density functional theory (DFT) and scanning tunneling microscopy (STM). Two stable adsorption positions that are found in DFT correspond to H atom attachment to an up-or down-buckled Ge dimer atom, respectively. Surprisingly, in the case where H bonds to the down-buckled Ge atom, we find that there is a redistribution of a unit of charge which leaves the net charge of the doubly occupied dangling bond of the unreacted Ge atom intact. This configuration is found to be the more stable of the two structures. Comparison to filled- and empty-state STM images confirms that this lowest energy structure is observed at room temperature. These results represent a fundamentally different picture of the physics and chemistry of H adsorption to Ge(001) compared with previous work.
使用密度泛函理论（DFT）和扫描隧道显微镜（STM）研究了孤立 H 原子在 Ge(001)表面的吸附。DFT 中发现的两种稳定吸附位置分别对应于 H 原子与上或下弯曲的 Ge 二聚体原子的附着。令人惊讶的是，在 H 与下弯曲的 Ge 原子键合的情况下，我们发现存在电荷的重新分布，这使得未反应的 Ge 原子的悬挂键的双重占据悬空键的净电荷保持不变。这种结构被发现是两种结构中更稳定的一种。与填充态和空态 STM 图像的比较证实，在室温下观察到这种最低能量结构。与以前的工作相比，这些结果代表了 H 吸附到 Ge(001)的物理和化学的根本不同的情况。
