Rotational alignment of NO from Pt(111). Inelastic scattering and molecular desorption
Rotational alignment of NO from Pt(111). Inelastic scattering and molecular desorption
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来自 Pt(111) 的 NO 的旋转排列。
DOI：
10.1039/f29898501325
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
R. Zare
中科院分区：
文献类型：
--
作者：
D. C. Jacobs;K. Kolasinski;R. Madix;R. Zare
NO分子与Pt（111）表面相互作用后，测量了NO分子的转动取向分布。用1 + 1共振增强多光子电离（REMPI）光谱探测了内态分布，其中NOA 2 <$+-X2 <$（0，0）带的谱线构成共振跃迁.研究了NO/Pt（111）的非弹性散射和捕获/脱附两种机制。在这两种情况下，对于J < 12.5，相对没有优先旋转对准。然而，具有较高旋转角动量的分子显示出对齐的显著增加。非弹性散射分子倾向于在垂直于表面的平面内旋转（“侧手翻”运动），而解吸分子倾向于在平行于表面的平面内旋转（“直升机”运动）。这些测量提供了新的洞察动量转移在表面和过渡态的性质，导致分子解吸。
The rotational alignment distribution of NO has been measured subsequent to the molecule's interaction with a well characterized Pt(111) surface. Internal state distributions have been probed using 1 + 1 resonance-enhanced multiphoton ionization (REMPI) spectroscopy in which lines of the NO A 2Σ+–X2Π(0, 0) band constitute the resonant transition. NO/Pt(111) scattering has been studied in two distinct regimes: inelastic scattering and trapping/desorption. In both cases, there is relatively no preferential alignment of rotation for J < 12.5. However, molecules with higher rotational angular momentum show a marked increase in alignment. Inelastically scattered molecules prefer to rotate in a plane normal to the surface (‘cartwheel’ motion), whereas desorbing molecules prefer to rotate in a plane parallel to the surface (‘helicopter’ motion). These measurements provide new insight into momentum transfer at surfaces and the nature of the transition state which leads to molecular desorption.