1] Radboud University Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands [2].
Radboud University Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
Nat Chem. 2014 Mar;6(3):216-21. doi: 10.1038/nchem.1860. Epub 2014 Feb 9.
Just as light scattering from an object results in diffraction patterns, the quantum mechanical nature of molecules can lead to the diffraction of matter waves during molecular collisions. This behaviour manifests itself as rapid oscillatory structures in measured differential cross-sections, and such observable features are sensitive probes of molecular interaction potentials. However, these structures have proved challenging to resolve experimentally. Here, we use a Stark decelerator to form a beam of state-selected and velocity-controlled NO radicals and measure state-to-state differential cross-sections for inelastic collisions of NO with He, Ne and Ar atoms using velocity map imaging. The monochromatic velocity distribution of the NO beam produced scattering images with unprecedented sharpness and angular resolution, thereby fully resolving quantum diffraction oscillations. We found excellent agreement with quantum close-coupling scattering calculations for these benchmark systems.
正如物体的光散射会产生衍射图案一样，分子的量子力学性质也会导致分子碰撞时物质波的衍射。这种行为表现为在测量的微分截面中出现快速振荡结构，而这些可观察到的特征是分子相互作用势能的敏感探针。然而，这些结构在实验上被证明难以解决。在这里，我们使用斯塔克减速器形成一束态选择和速度控制的 NO 自由基，并使用速度映射成像测量 NO 与 He、Ne 和 Ar 原子非弹性碰撞的态到态微分截面。NO 束的单色速度分布产生了具有前所未有的清晰度和角分辨率的散射图像，从而完全分辨出量子衍射振荡。我们发现这些基准系统的量子紧密耦合散射计算结果非常吻合。
