C(2×2)S/Fe(001)吸附体系的SCF-X_α-MS研究

THE SCF-X_α-MS STUDIES ON THE CHEMISORPTION SYSTEM OF C(2×2) S/Fe(001)

采用SCF-X_α-MS方法,对于C(2×2)S/Fe(001)吸附体系,选择Fe_5S和Fe_9S两种原子簇模型,研究了该吸附体系的电子结构、吸附成键特征及其相互作用图象。结果表明,S吸附于Fe(001)单晶表面具有较强的定域性质,S原子与底物Fe原子之间的吸附相互作用主要表现为S(3p)-Fe(4s,3d)之间的轨道相互作用。通过对表面吸附键长的优化,其结果与X.S.Zhang等的ARPEFS的实验结果一致。

In this paper, two kinds of appropriate cluster model Fe_5S and Fe_9S are chosen for the chemisorption system of C(2×2)S/Fe(001), The electronic structure of these two clusters, the characterics of chemisorption bonding and the picture of adsorption interaction were sutdied using SCF-X_α-MS method. Results show that adsorption of sulfur on Fe(001) single crystal surface has strong Iocal effect and sulfer 3P_x, 3P_y orbitals hybridize with the first layer iron 3d_(xz), 3d_(yz), and sulfur, 3P_z may interact with a second layer iron 4s and 3d_z2. The optimized ehemisorption geomtries are in fair agreement with ARPEFS result of C(2×2)S/Fe(001) by X. S. Zhang et al.