Atomic and electronic structures of oxygen-adsorbed Si(001) surfaces.
Atomic and electronic structures of oxygen-adsorbed Si(001) surfaces.
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DOI：
10.1016/0039-6028(96)80076-8
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发表时间：
1996-03
期刊：
影响因子：
--
通讯作者：
Uchiyama;Tsukada
中科院分区：
文献类型：
--
作者：
Uchiyama;Tsukada
我们研究了氧吸附的 Si (001) 表面的稳定结构及其电子态。在本研究中，应用了具有超软赝势方案的第一原理分子动力学方法。根据计算出的原子力，氧和硅原子完全松弛，以获得优化的几何形状。我们发现了原子氧吸附的三个（元）稳定位点：一个二聚体桥位点和二聚体原子的两个不同的背键位点。原始二聚体键分别被分解或保留和扭曲。最有利的是下二聚体原子的背键位点。在这里，氧的电负性增强了二聚体键的离子性。此外，我们模拟了氧吸附表面的扫描隧道显微镜图像。最稳定几何结构的特征与观察到的特征非常一致。© 1996 美国物理学会。
We investigate the stable structures of oxygen-adsorbed Si (001) surfaces and their electronic states. For this study, the first-principles molecular-dynamics method with the ultrasoft pseudopotential scheme is applied. The oxygen and silicon atoms are fully relaxed according to the calculated atomic forces for the optimized geometries. We find three (meta) stable sites for atomic oxygen adsorption: a dimer-bridge site and two different backbond sites of the dimer atoms. The original dimer bond is decomposed, or preserved and twisted, respectively. Most energetically favorable is the backbond site of the down dimer atom. Here, the electronegativity of oxygen enhances the ionicity of the dimer bond. Further, we simulate scanning tunneling microscopy images of the oxygen-adsorbed surfaces. The features of the most stable geometry are in good agreement with the observed ones.© 1996 The American Physical Society.