Simple Atoms on Metal Surfaces

w：\awards\awards96\*.doc 9629715 Diehl 该研究计划涉及低能电子衍射（LEED）和氦原子散射（HAS）实验，以及碱金属原子和稀有气体原子在金属表面的分子动力学模拟。我们的目标是增加我们的理解的相互作用和属性，引起的表面原子的平衡结构。该方法是确定结构，振动振幅和它们的温度依赖性的公度结构使用动态LEED。这些覆盖层上的缺陷，如步骤的影响也将被调查，和新的LEED计算技术将开发这些系统。 此外，将进行研究，以了解在无公度层的旋转外延的作用。 %这个研究项目涉及到当钾或氙等简单原子吸附在银或铜等金属表面时所形成的结构的研究。它们的结构将通过使用电子或氦原子的衍射来确定。 当简单原子被吸附在表面上时，形成的结构可以具有与它们被吸附的表面相同的周期性，或者具有不同的周期性。 通过测量这种周期性，我们获得了这些原子如何与表面相互作用的信息。吸附原子的这种基本相互作用是有趣和有用的，从学习如何制造更好的计算机芯片到发明测量表面张力的仪器。 ***

w:\awards\awards96\*.doc 9629715 Diehl This research program involves low energy electron diffraction (LEED) and helium atom scattering (HAS) experiments, as well as molecular dynamics simulations, of alkali metal atoms and rare gas atoms on metal surfaces. The goal is to increase our understanding of the interactions and properties which give rise to the equilibrium structures of atoms at surfaces. The approach is to determine the structures, the vibrational amplitudes and their temperature dependence in commensurate structures using dynamical LEED. The effects of defects such as steps on these overlayers will also be investigated, and new LEED calculational techniques will be developed for these systems. Additionally, studies will be made in order to understand the role of corrugation in the rotational epitaxy of incommensurate layers . %%% This research program involves the study of the structures which form when simple atoms such as potassium or xenon are adsorbed on metal surfaces such as silver or copper. Their structures will be determined by using the diffraction of electrons or helium atoms. When simple atoms are adsorbed on surfaces, the structures which form may have the same periodicity as the surface on which they are adsorbed, or a different periodicity. By measuring this periodicity, we obtain information on how these atoms interact with the surface. Such fundamental interactions of adsorbed atoms are interesting and useful for reasons as diverse as learning how to build better computer chips to inventing an instrument to measure surface tension. ***