Multiple—Scattering of Near—Edge x—ray Absorption Fine Structure of Sulphur—Passivated InP（100） Surface

We use the multiple-scattering cluster method to calculated the sulphur 1s near-edge x-ray absorption fine structure (NEXAFS) of S-passivated InP(100) surface.The physical origins of the resonances in the NEXAFS have been unveiled.It is shown that the most important resonance is attributed to the photoelectron scattering between the central sulphur and the nearest indium atoms.The studies show that two S-S dimers with the bond lengths of 2.05A and 3.05A coexist in the surface,meanwhile the bridge and antibridge site adsorption of single S could not be ruled out.We support the scanning tunnelling microscopy result that the S-passivated InP(100) surface exhibits significant discorder.     

多重散射团族理论对CO／NiO（100）NO／NiO（100）吸附系统的分析与比较

用多理散射团族（ＭＳＣ）理论对ＣＯ／ＮｉＯ（１００）和ＮＯ／ＮｉＯ（１００）吸附系统的Ｃ１ｓ近边Ｘ射线吸收精细结构（ＮＥＸＡＦＳ）和Ｎ１ｓ ＮＥＸＡＦＳ谱进行了详细的计算和分析。理论计算表明ＣＯ／ＮｉＯ（１００）是弱物理吸附,ＣＯ分子与表面的多极静电相互作用很弱,σ共振不依赖Ｃ－Ｏ键长的变化,ＭＳＣ方法分析表明,ＣＯ是以Ｃ原子朝下,吸附在衬底的Ｎｉ－Ｏ键上,可靠性因子计算显示Ｃ原子的吸附位置距Ｎｉ