【摘要】 （ＣＯ＋Ｃｓ）／Ｒｕ（１０１０）共吸附的体系中，ＣＯ分子由于受Ｃｓ原子强烈影响，分子轨道发生 重新杂化组合．ＣＯ分子原来在清洁 Ｒｕ（１０１０）表面上结合能位于 ７．５ｅＶ处相重叠的５σ和 １π轨道 对应谱峰分裂为两峰，结合能分别位于 ６.３和 ７．８ ｅＶ处．其中 ６．３ ｅＶ处的谱峰来自ＣＯ分子 １π 轨道 的一支，它显示出该分子轨道沿衬底<０００１>晶向的镜面反对称性．ＣＯ分子１π轨道的另一支和５σ 轨道在结合能 ７．８ ｅＶ处相重叠．更多还原

【Abstract】 The molecular orbits of CO are rearranged under the strong influence of coadsorbed Cs atoms. HREELS study shown that there are two molecular adsorption states of CO on a Cs pre-covered Ru（1010） surface. One with high C-O stretch frequency similar to that on dean Ru （1010） surface, the other with low C-O stretch frequency due to the strong shoft-range interaction between the CO molecule and the Cs atom. ARUPS experiment results shown the peak for CO on dean Ru（1010） surface, at 7.5eV BE attributed to the 5σ and 1π orbits, is split into two peaks with one at 6.3eV BE and the other at 7.8eV BE. Two concrete models has been proposed to describe the short-range alkali metal-CO interaction, the sp² rehybridization model and the direct interaction model. The experiment results confirm that the sp² rehybridization model must be reasonable. According this model, the Me-CO bond rehybridizes to sp² forming new a and π bonds (a₁, b₁, b₂ orbits in the C_2v point group) According The p-polarized ARUPS results, the peak at 6.3eV BE, comes from one of a π type 1b₂, orbits, shows an anti-symmetry character about the plane parallel to the <0001> crystallographic direction in the surface. Another π type orbit 1b₁ is still at 7.8eV BE overlapping with 5a₁ orbit.更多还原