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利用第一性原理的离散变分局域密度泛函方法，采用团簇模型（Ｓｉ３４Ｈ３６Ｗ１１）来模拟ＳＴＭ操纵Ｓｉ（１１１）７×７表面顶角吸附原子的过程．通过分析在进行原子操纵过程中体系的能量与电子云密度分布来研究针尖和外电场的作用．结果表明，当针尖与样品间距离较近时，利用两者间有较强的相互作用，能有效地降低脱出能的能垒高度．外电场对体系脱出能的影响与其大小及极性有关，当样品上所加正偏压增强时，脱出能曲线高度单调下降，而外电场极性为负时，反而稍有增高．仅考虑针尖和样品之间的静态电子相互作用及静电场的作用，尚不能使被操纵原子脱离样品表面．最后讨论了在Ｓｉ（１１１）７×７表面上进行原子操纵的其他机理
Using the first-principles discrete-variational local density functional method, cluster model (Si34H36W11) was used to simulate the process of STM manipulation of Si (111) 7 × 7 surface apex. The role of the tip and the external electric field is studied by analyzing the distribution of energy and electron cloud density during the atomic manipulation. The results show that when the distance between the tip and the sample is close, the strong interaction between the tip and the sample can effectively reduce the energy barrier height of the prolapse energy. The influence of the external electric field on the system prolaction energy is related to its size and polarity. When the positive bias voltage applied to the sample increases, the prolapse energy curve decreases monotonically, but increases slightly when the external field polarity is negative. Considering only the static electronic interaction between the tip and the sample and the action of the electrostatic field, it is not yet possible to detach the manipulated atom from the sample surface. Finally, other mechanisms of atomic manipulation on Si (111) 7 × 7 surface are discussed