Si(111)7×7结构模型的稳定性研究  

THE STABILITY OF STRUCTURE MODELS OF Si(111) 7×7 SURFACE

作　　者：刘惠周 李哲吟[1] 

机构地区：[1]中山大学物理系

出　　处：《物理学报》1989年第10期1569-1577,共9页Acta Physica Sinica

基　　金：国家自然科学基金

摘　　要：本文基于有相互作用的结构件的概念,对Si(111)7×7结构模型的稳定性进行研究。利用紧束缚法,计算了各种结构件的形成能及其相互作用能。由这些结构件可灵活地构成各种大单胞的表面结构并对其进行总能计算,而避免了大工作量的计算。对Si(111)5×5和7×7 DAS模型,我们得到其表面能分别为-0.467eV和-0.477eV,与Qian和Chadi的结果很接近。并指出,Harrison提出的7×7吸附原子模型和Binnig等人提出的7×7吸附原子-空位模型都是不稳定的。In this paper, based on the concept of building blocks with interactions, we study the stability of models of Si(lll) 7×7 reconstructed surface. With use of tight-binding method, we calculated formation energies of various building blocks and their interactions. With these building blocks, various large unit surfaces can be constructed and their total energies can be easy estimated, without heavy calculations. We evaluate the surface energies of Si(lll) 5×5 and 7×7 DAS models, and get the results of -0.467 eV and -0.477 eV, respectively, close to the results of Qian and Chadi~[3]. Moreover, we point out that neither the 7×7 adatom model~[16] nor the 7×7 adatom-vacancy model~[2] are stable.

关 键 词：结构模型 表面物理学 SI(111) 稳定 

分 类 号：O484.1[理学—固体物理]