Kim C M, Yi C-W, Goodman D W
Department of Chemistry, Texas A and M University, College Station, Texas 77842-3012, USA.
J Phys Chem B. 2005 Feb 10;109(5):1891-5. doi: 10.1021/jp045947s.
Infrared reflection absorption spectroscopy (IRAS) has been used to study CO-NO and CO-O(2) interactions on Cu(100) between 25 and 200 K. A strong repulsive interaction between CO and NO on Cu(100) at 25 K causes tilting of the CO molecules away from the surface normal and a blue-shift of the CO vibrational frequency. Upon warming and decomposition of the NO, the CO molecules return to a bonding position normal to the surface plane. The vibrational frequency of CO blue-shifts from 2087 to 2136 cm(-1) upon coadsorption with N and O atoms formed from NO decomposition. On the other hand, the interaction of CO with O(2) at 27 K on Cu(100) in the submonolayer regime induces a red-shift of the CO vibrational frequency. Atomic oxygen, formed on Cu(100) by dissociation of O(2) at 95 K, induces a blue-shift of the vibrational frequency of coadsorbed CO to 2116 cm(-1). The CO vibrational frequency shifts to 2091 cm(-1) when the surface is annealed to 140 K, implying a change in the adsorption geometry of the oxygen atoms on Cu(100).
红外反射吸收光谱（IRAS）已被用于研究25至200K温度范围内Cu(100)表面上CO-NO和CO-O₂的相互作用。在25K时，Cu(100)表面上的CO和NO之间存在强烈的排斥相互作用，导致CO分子倾斜远离表面法线方向，并使CO振动频率发生蓝移。随着NO升温并分解，CO分子回到垂直于表面平面的键合位置。与由NO分解形成的N和O原子共吸附时，CO的振动频率从2087 cm⁻¹蓝移至2136 cm⁻¹。另一方面，在亚单层状态下，27K时CO与O₂在Cu(100)表面的相互作用会导致CO振动频率发生红移。95K时，O₂在Cu(100)表面解离形成的原子氧会使共吸附的CO振动频率蓝移至2116 cm⁻¹。当表面退火至140K时，CO振动频率移至2091 cm⁻¹，这意味着Cu(100)表面上氧原子的吸附几何结构发生了变化。
