Temporal and local reduction of a potential energy well under dynamic equilibrium: CO on Ni(100).
Temporal and local reduction of a potential energy well under dynamic equilibrium: CO on Ni(100).
复制标题
动态平衡下势能井的时间和局部还原：Ni(100) 上的 CO。
DOI：
10.1103/physrevlett.73.292
复制
发表时间：
1994
影响因子：
8.6
通讯作者：
Kawai
中科院分区：
文献类型：
--
作者：
Takagi;Yoshinobu;Kawai
通过时间分辨红外反射吸收光谱在350至400 K的几个温度下直接观察预吸附的$^{13}\mathrm{C}$$^{18}\mathrm{O}$和气相$^{12}\mathrm{C}$$^{16}\mathrm{O}$之间的动态平衡，发现气相CO下的解吸过程由于两者之间的排斥相互作用而增强。预吸附的 $^{13}\mathrm{C}$$^{18}\mathrm{O}$ 和事件 $^{12}\mathrm{C}$$^{16}\mathrm{O}$ 分子从气相到达吸附 CO 的附近位置。因此，活化能从 127 kJ ${\mathrm{mol}}^{\ensuremath{-}1}$ 降低，真空解吸值可达 25 kJ ${\mathrm{mol}}^{\ensuremath{-}1}$，即使 $\ensuremath{\theta}=0.1\ensuremath{-}0.3$ 单层 (ML) 和 CO 通量为 0.001 ML${\mathrm{s}}^{\ensuremath{-}1}$。
Direct observation of dynamic equilibrium between preadsorbed $^{13}\mathrm{C}$$^{18}\mathrm{O}$ and gas phase $^{12}\mathrm{C}$$^{16}\mathrm{O}$ by means of time-resolved infrared reflection absorption spectroscopy at several temperatures from 350 to 400 K reveals that the desorption process under gas phase CO is enhanced due to the repulsive interaction between preadsorbed $^{13}\mathrm{C}$$^{18}\mathrm{O}$ and incident $^{12}\mathrm{C}$$^{16}\mathrm{O}$ molecules from the gas phase arriving at nearby sites of adsorbed CO. As a result, the activation energy is reduced from 127 kJ ${\mathrm{mol}}^{\ensuremath{-}1}$, the value for desorption into vacuum, to 25 kJ ${\mathrm{mol}}^{\ensuremath{-}1}$ even for $\ensuremath{\theta}=0.1\ensuremath{-}0.3$ monolayer (ML) and a CO flux of 0.001 ML${\mathrm{s}}^{\ensuremath{-}1}$.