中国物理B ›› 2012, Vol. 21 ›› Issue (6): 67302-067302.doi: 10.1088/1674-1056/21/6/067302
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇 下一篇
李敏a, 张俊英a, 张跃b, 王天民a
Li Min(李敏)a), Zhang Jun-Ying(张俊英) a)† Zhang Yue(张跃)b), and Wang Tian-Min(王天民)a)
摘要: The adsorptions of CO and O2 molecules individually on the stoichiometric Cu-terminated Cu2O (111) surface are investigated by first-principles calculations on the basis of the density functional theory. The calculated results indicate that the CO molecule preferably coordinates to the Cu2 site through its C atom with an adsorption energy of -1.69 eV, whereas the O2 molecule is most stably adsorbed in a tilt type with one O atom coordinating to the Cu2 site and the other O atom coordinating to the Cu1 site, and has an adsorption energy of -1.97 eV. From the analysis of density of states, it is observed that Cu 3d transfers electrons to 2π orbital of the CO molecule and the highest occupied 5σ orbital of the CO molecule transfers electrons to the substrate. The sharp band of Cu 4s is delocalized when compared to that before the CO molecule adsorption, and overlaps substantially with bands of the adsorbed CO molecule. There is a broadening of the 2π orbital of the O2 molecule because of its overlapping with the Cu 3d orbital, indicating that strong 3d-2π interactions are involved in the chemisorption of the O2 molecule on the surface.
中图分类号: (Surface states, band structure, electron density of states)