Temperature dependent stereodynamics in surface scattering measured through subtle changes in the molecular wave function
Temperature dependent stereodynamics in surface scattering measured through subtle changes in the molecular wave function
复制标题
通过分子波函数的细微变化测量表面散射中的温度依赖性立体动力学
DOI：
10.1039/d4fd00007b
复制
发表时间：
2024
影响因子：
3.4
通讯作者：
Chadwick H
中科院分区：
文献类型：
--
作者：
Chadwick H
利用磁操纵分子束技术改变了H2分子与阶梯状Cu（511）表面碰撞时的旋转取向，并研究了散射到镜面通道中的分子的偏振依赖性随表面温度的变化。在所有温度下，像侧手翻一样旋转的H2分子比像直升机一样旋转的H2分子更容易散射到镜面通道中。此外，散射的分子更有可能像侧手翻一样旋转，而不管它们在碰撞前的状态如何。增加Cu（511）表面的温度导致极化效应变得更强，散射对具有侧手翻状旋转的H2变得更具选择性。因此，从Cu（511）表面散射H2分子束并将散射的分子带入镜面通道提供了一种产生旋转偏振H2束的方法，其中可以通过改变表面温度来调节偏振。相反，在相同的温度范围内，从平坦的Cu（111）表面的镜面散射观察到的旋转取向依赖性与表面温度无关。
A magnetically manipulated molecular beam technique is used to change the rotational orientation of H2 molecules which collide with a stepped Cu(511) surface and explore how the polarisation dependence of molecules scattering into the specular channel changes as a function of surface temperature. At all temperatures, H2 molecules that are rotating like cartwheels are more likely to be scattered into the specular channel than those that are rotating like helicopters. Furthermore, the scattered molecules are more likely to be rotating like cartwheels, regardless of their state before the collision. Increasing the temperature of the Cu(511) surface causes the polarisation effects to become stronger, with the scattering becoming more selective for H2 with cartwheel like rotation. Therefore, scattering a molecular beam of H2 from a Cu(511) surface and taking the molecules scattered into the specular channel provides a method to create a rotationally polarised beam of H2, where the polarisation can be tuned by changing the surface temperature. In contrast, the rotational orientation dependence observed for specular scattering from a flat Cu(111) surface is independent of surface temperature within the same temperature range.