采用改进分析型嵌入原子法计算了Pt(110)表面自吸附原子的能量和法向力。当Pt吸附原子位于Pt(110)表面第一层原子的二重对称洞位上0.11nm时最稳定。Pt吸附原子的最佳迁移路径是由一个二重对称洞位沿密排方向迁移到最近邻的另一个二重对称洞位。在吸附原子远离表面的过程中,将依次经过排斥、过渡和吸引等三个区域。在排斥区和过渡区,由于吸附原子与表面原子间强的相互作用势,吸附原子的能量和法向力的形貌图均为(110)面原子排列的复形,与对势理论和嵌入原子法得到的结果一致。在吸引区,由于多体相互作用及晶体中原子电子密度的非球型对称分布影响的相对增强,使吸附原子的能量和法向力的形貌图更加复杂。
The energy and normal force of self-adatom on Pt(110) surface have been calculated by the modified analytical embedded atom method. The most stable position for a Pt adatom on Pt(II0) surface is O. 11 nm above the hollow of the first layer atoms, and the best path for a Pt adatom migrating from a hollow to neighbor hollow is along the close-packed direction. On leaving the surface, the adatom will go through the repulsive, transitional and attractive regions, successively. In the repulsive and transitional regions, due to stronger pair interaction potential between adatom and the first layer atoms, the contour maps of the energy and normal force could be seen simply as a duplicate of the Pt(II0) surface. This is consistent with the results of pair potential theory and embedded atom method. The complicated contour maps of the energy and normal force were obtained in the attractive region due to relatively increasing effects of the many-body interactions and nonspherical distribution of the electrons of the atoms in the crystal.