Dynamical nature of the high-temperature Pb/Si(111)-1x1 phase

Article

关键词: SURFACE SPECTROSCOPY;    PB;    SI(111);    TRANSITIONS;    WAVE;    STM;   

DOI  :  10.1103/PhysRevB.84.155422

来源: SCIE

【 摘 要 】

Temperature-induced structural change of the Pb/Si(111)-root 7 x root 3 surface has been studied by using ab initio molecular dynamics simulations. The ordered root 7 x root 3 surface is found to evolve into a diffusive phase at elevated temperatures. Identified as responsible for the diffusive phase is a low-barrier concerted motion of two Pb atoms, one located on a hollow site and the other on an adjacent on-top site, which leads to an effective hollow-to-hollow Pb diffusion occurring in the background 1 x 1 lattice of the on-top Pb atoms. This diffusion picture explains well the 1 x 1 diffraction pattern with diffuse streaks observed in the high-temperature phase of the root 7 x root 3 surface and is proposed as the common structural and dynamical feature of all the high-temperature Pb/Si(111)-1 x 1 phases evolving from different ordered phases.

【 授权许可】

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