Department of Physics, King's College London, The Strand, London WC2R 2LS, UK.
J Phys Condens Matter. 2010 Jul 7;22(26):265001. doi: 10.1088/0953-8984/22/26/265001. Epub 2010 May 24.
The InSb(001) surface has been studied experimentally, using room temperature scanning tunnelling microscopy (RT STM), and theoretically, using ab initio density functional theory (DFT) calculations. RT experimental STM images show bright lines running along the bulk crystal [110] direction. Resolved features between the bright lines whose appearance depends on the applied bias voltage confirm clearly the c(8×2) reconstruction of this surface. Our calculations, which are reported for this surface for the first time, include the reconstructed 4×2 and c(8×2) surfaces, the latter according to the so-called ζ-model proposed previously by Lee et al and Kumpf et al. A 'defective' structure proposed previously by Kumpf et al, which contains an extra In atom within a top bilayer is also considered. In all cases, we obtained stable structures. Calculated STM images for the c(8×2) reconstruction obtained using the Tersoff-Hamann approximation compare extremely well with the experimental ones. We also find that the defect structure may not be clearly visible in the STM images. Finally, a brief discussion is given on the other, although closely related, phase of the same surface observed previously in low temperature (LT) experimental STM images (Goryl et al 2007 Surf. Sci. 601 3605).
InSb(001) 表面已经通过室温扫描隧道显微镜 (RT STM) 进行了实验研究，并通过从头算密度泛函理论 (DFT) 计算进行了理论研究。RT 实验 STM 图像显示出沿体晶 [110] 方向延伸的亮线。亮线之间分辨出的特征，其外观取决于施加的偏置电压，这清楚地证实了该表面的 c(8×2) 重构。我们的计算首次针对该表面进行了报道，包括重构的 4×2 和 c(8×2) 表面，后者根据 Lee 等人和 Kumpf 等人之前提出的所谓 ζ 模型。Kumpf 等人之前提出的一种“缺陷”结构也被考虑在内，其中包含一个额外的顶层内的 In 原子。在所有情况下，我们都得到了稳定的结构。使用 Tersoff-Hamann 逼近计算的 c(8×2) 重构的 STM 图像与实验图像非常吻合。我们还发现，缺陷结构在 STM 图像中可能不太明显。最后，简要讨论了之前在低温 (LT) 实验 STM 图像中观察到的同一表面的另一个（尽管密切相关）相 (Goryl 等人，2007 年，Surf. Sci. 601, 3605)。
