Theory of Physically Adsorbed Layers

一个关于结构的理论研究计划， 描述了薄物理吸附层的热力学。 主要目标是实现对几个 吸附物/基质组合，其中最近的实验 数据显示，竞争的空间周期性的影响， 吸附层晶格和衬底晶格。 几个主题是 这可能会导致改进的规格， 吸附原子横向运动的能垒 衬底表面。 所考虑的衬底是（111）面 铂的基底平面表面、石墨的基底平面表面和（001） 氧化镁的表面。 吸附物包括氙、氪 以及分子氢和氮。 计算包括 氢原子基态的变分量子力学 氘和晶格动力学和细胞模型近似 对于近经典吸附物。 拟议的工作依赖于 在很大程度上从低的改进获得的实验数据 能量电子衍射，x射线衍射，热中子 散射和热氦原子散射。

A program of theoretical research on the structures and thermodynamics of thin physically adsorbed layers is described. The main goal is to achieve a quantitative understanding of a few adsorbate/substrate combinations in which recent experimental data show effects of the competing spatial periodicity of an adlayer lattice and the substrate lattice. Several topics are described which could lead to improved specification of the energy barriers to lateral motion of adsorbed atoms on the substrate surface. The substrates considered are the (111) face of platinum, the basal plane surface of graphite and the (001) face of magnesium oxide. The adsorbates include xenon, krypton and molecular hydrogen and nitrogen. The calculations include variational quantum mechanics for the ground state of hydrogen and deuterium and lattice dynamics and cell model approximations for the near classical adsorbates. The proposed work relies heavily on experimental data obtained from refinements of low energy electron diffraction, x-ray diffraction, thermal neutron scattering, and thermal helium atom scattering.