High Resolution Low Energy Electron Diffraction Studies of Surface and Overlayer Ordering

支配平衡的基本物理定律， 非平衡集体现象的清洁表面附近的 熔化温度，和吸附的覆盖层将是 使用高分辨率低能电子 衍射技术（HRLEED）。 他们建议研究这种变化 清洁金属的结构和热力学性质 使用HRLEED在表面粗糙化/熔化过程中进行表面处理。 研究工作将包括：（1）确定性质 以及缺陷密度的测量 在熔融温度附近的表面产生;（2） 短程相关和临界相关的测量 与表面粗糙化/熔化阶段相关的指数 过渡 对于吸附的覆盖层，研究工作将 包括（1）定量测定覆盖层畴生长 在统计力学状态的松弛期间， （2）二维动力学标度理论的检验， 基态简并覆盖层的普适性 大于2;和（3）杂质的影响（随机场） 系统的二维相变和畴生长 基态简并度大于2。 的结果 研究不仅能帮助我们深入了解 描述清洁表面的幂律、比例律和生长律 和吸附的上层秩序，但也将增加我们的 控制重要实际过程的知识，如 晶体生长和多相催化。

The fundamental physical laws that govern the equilibrium and non-equilibrium collective phenomena of a clean surface near the melting temperature, and of an adsorbed overlayer will be investigated using the high resolution low-energy electron diffraction technique (HRLEED). They propose to study the change of structural and thermodynamic properties of clean metal surfaces during surface roughening/melting using HRLEED. Research efforts will include: (1) identification of the nature of the disorder and measurement of the density of defects generated at the surface near the melting temperature; (2) measurement of the short range correlations and critical exponents associated with the surface roughening/melting phase transition. For an adsorbed overlayer, research efforts will include (1) quantitative determination of overlayer domain growth during the relaxation of statistical mechanical states far from equilibrium; (2) testing of 2-D kinetic scaling theory and universality for an overlayer with ground state degeneracy greater than two; and (3) effects of impurities (random fields) on 2-D phase transitions and domain growth of a system with ground state degeneracy greater than two. The results of this research will not only help us gain insight into the fundamental power, scaling and growth laws which describe the clean surface and adsorbed overlayer ordering, but will also increase our knowledge in controlling important practical processes such as crystal growth and heterogeneous catalysis.