The Influence of Structure on the Itinerant Band Structure of Thin Metal Overlayers

通过改变晶体结构和晶格参数，可以改变薄膜覆盖层的电子能带结构。结合角分辨光电发射和低能电子衍射（LEED）等强大的表面科学技术，研究晶体和能带结构之间的相关性。通过在精心选择的晶体衬底上外延生长覆盖层，覆盖层将被迫形成不寻常的晶体几何形状和晶格间距。研究将集中在从IIa和IIb元素和惰性气体中选择的涂层材料上。利用光电发射法可以测定价带结合能与布里渊带位置的关系，从而研究复层的能带结构。这种确定能带结构的传统技术将被一种新的方法所补充，这种方法包括分析价轨道的相对光电离部分截面作为光子能量的函数。LEED将通过比较LEED强度与电子加速电压与动态LEED计算来研究外层晶格结构。通过结合光发射和原子束散射两种技术研究薄（0-10）单层薄膜，将深入了解原子轨道重叠和许多电子效应对电子能带结构的重要性。

The electronic band structure of thin film overlayers can be altered by changing the crystal structure and lattice parameters. The correlation between crystal and band structures will be investigated by combining the powerful surface science techniques of angle-resolved photoemission and low energy electron diffraction (LEED). Overlayers will be forced into unusual crystal geometries and lattice spacings by epitaxially growing the overlayer on carefully chosen crystal substrates. The investigation will concentrate on selected overlayer materials chosen from the IIa and IIb elements and the noble gases. The band structure of the overlayers can be investigated by using photoemission to determine the binding energies of the valence bands as a function of the position in the Brillouin zone. This traditional technique of determining band structure will be complemented by a new method that consists in analyzing the relative photo-ionization partial cross-section of valence orbitals as a function of photon energy. LEED will be used to investigate the overlayer crystal lattice structure by comparing LEED intensity versus electron accelerating voltages with dynamical LEED calculations. By combining the two techniques of photoemission and atom beam scattering in the investigation of thin (0-10) monolayer films, insight into the importance of atomic orbital overlap and many electron effects upon electronic band structure will be provided.