Helium Diffraction as a Probe of Structure and Proton Order on Model Ice Surfaces
Helium Diffraction as a Probe of Structure and Proton Order on Model Ice Surfaces
复制标题
DOI：
10.1021/acs.jpclett.6b02221
复制
发表时间：
2016-11-17
影响因子：
5.7
通讯作者：
Allison, W.
中科院分区：
文献类型：
--
作者：
Avidor, N.;Allison, W.
氦衍射具有揭示冰表面质子有序程度的潜力，并在过去被用于基准理论工作。我们证明，以前的计算不能充分反映衍射实验的精度。通过使用精确的紧密耦合方法将现实的氦-水势与量子计算相结合，我们证明了散射是强烈的能量依赖。从氦原子的选择性吸附共振中可以最好地推断出质子的顺序，这涉及到多次散射。我们用这些结果讨论了冰h表面关于质子有序的最新假设的有效性。
Helium diffraction has the potential to reveal the degree of proton order at an ice surface, and has been used in the past to benchmark theoretical work. We demonstrate that previous calculations do not represent the diffraction experiment to a sufficient degree of accuracy. By combining a realistic helium-water potential with quantum calculations using exact close-coupling methods we demonstrate that the scattering is strongly energy dependent. Proton order may be inferred best from selective adsorption resonances of the helium atom, which involve multiple scattering. We use the results to discuss the validity of the latest assumptions for the ice Ih surface with respect to proton ordering.