【摘要】 应用原子和表面簇合物相互作用的5参数Morse势方法(简称5MP)构造了SNi表面簇合物体系的解析势函数.首先对SNi低指数表面体系进行了研究,并获得了全部临界点性质.计算结果表明硫原子在Ni(100)面上的稳定吸附态为四重洞位,在Ni(111)面上,硫原子吸附于三重位,硫原子在Ni(110)面上的吸附位有所变化.第一与第二周期的原子在(110)面上的稳定吸附态大都为赝式三重位和长桥位,而硫原子却吸附在Ni(110)面的四重洞位.理论分析结果和实验推测结果符合得很好.同时,还对SNi(311)台阶面吸附体系进行了研究.理论结果表明SNi(311)表面吸附体系只存在四重吸附态和hcp三重吸附态,fcc三重吸附态在和四重吸附态的竞争中完全湮灭.对于SNi表面吸附体系,理论结果给出S原子的表面吸附结合能和表面簇合物的粗糙度有关.结合能从小到大的顺序为(111)<(100)<(110)<(311).更多还原

【Abstract】 The 5 parameter Morse potential (for short 5 MP) of the interaction between S atom and Ni surface has been constructed. The adsorption of S atom on Ni low index surface was investigated and all critical characteristics were obtained. The calculated results indicate: S atom is located at the fourfold hollow site on the Ni(100) surface and at the threefold hollow site on the Ni(111) surface. On the Ni(110) surface, S atom is located at the fourfold hollow site, which is different from the nonmetal atom in the first and second period that is located at the pseudo threefold hollow site and long bridge site on the Ni(110) surface. Our theoretical results are in accord with experimental data. Moreover, the adsorption of S atom on the Ni(311) step surface was also researched. The calculated results show: S atom is located at the fourfold hollow site and hcp threefold hollow site, while the fcc threefold hollow site is annihilated during completing with the fourfold hollow site. For the S Ni system, the binding energy is ordered as (111)<(100)<(110)<(311), and our calculated results reveal that the surface binding energy of the S atom is relevant to the coarse degree of cluster surface.更多还原