Department of Physics, AlbaNova University Center, Stockholm University, SE-10691, Sweden.
SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA.
Science. 2015 Feb 27;347(6225):978-82. doi: 10.1126/science.1261747. Epub 2015 Feb 12.
Femtosecond x-ray laser pulses are used to probe the carbon monoxide (CO) oxidation reaction on ruthenium (Ru) initiated by an optical laser pulse. On a time scale of a few hundred femtoseconds, the optical laser pulse excites motions of CO and oxygen (O) on the surface, allowing the reactants to collide, and, with a transient close to a picosecond (ps), new electronic states appear in the O K-edge x-ray absorption spectrum. Density functional theory calculations indicate that these result from changes in the adsorption site and bond formation between CO and O with a distribution of OC-O bond lengths close to the transition state (TS). After 1 ps, 10% of the CO populate the TS region, which is consistent with predictions based on a quantum oscillator model.
飞秒 X 射线激光脉冲用于探测在光学激光脉冲引发下的一氧化碳（CO）在钌（Ru）上的氧化反应。在几百飞秒的时间尺度上，光学激光脉冲激发 CO 和氧（O）在表面上的运动，使反应物碰撞，并在瞬态接近皮秒（ps）时，新的电子态出现在 O K 边 X 射线吸收光谱中。密度泛函理论计算表明，这些是由于 CO 和 O 的吸附位置和键形成的变化引起的，OC-O 键长的分布接近过渡态（TS）。在 1 ps 后，有 10%的 CO 占据 TS 区域，这与基于量子振荡器模型的预测一致。
