氧原子在钨低指数表面及(211)高指数表面上的吸附和振动

 应用原子和表面簇合物相互作用的5参数Morse势方法研究了氧原子在W低指数表面及(211)高指数表面上的吸附和振动. 计算结果表明,低覆盖度下,在W(100)面氧原子吸附在四重洞位,随着覆盖度增加,(100)面发生缺行重构,膺式三重位为稳定吸附位; 在W(110),(111)及(211)面,氧原子均趋向于吸附在膺式三重位. 该计算结果和实验符合得很好.

Adsorption and Vibration of O Atom on W Low-Index and (211) High-Index Surfaces

The adsorption and diffusion of O atom on W low-index surfaces and W(211) high-index surface were investigated by 5-parameter Morse potential in detail. The calculated results show that O atom is only located at the four-fold hollow site of the intact W(100) surface. With increasing the O coverage, a missing-row reconstruction that happened on W(100) and quasi-triple-fold site was the most stable adsorption site. On W(110), O atom is adsorbed preferentially on pseudo-triple-fold site, and the perpendicular vibration is 68.7 meV. On W(111), O atom is also tended to occupy quasi-triple-fold site with a perpendicular vibration mode at 72.9 meV. On the W(211) surface, the quasi-triple-fold site is the more favorable one for O atom adsorption, and the parallel and perpendicular vibration frequencies are 60.7, 43.1 and 75.5 meV, respectively. The obtained data is in good agreement with the experimental results.