Auger-Photoelectron Coincidence Spectroscopy Studies of Surface Alloys, Ultrathin Metal Films, and Layered Compounds

这个实验研究项目涉及使用俄歇-光电子符合谱(APECS)进行表面分析，重点研究表面合金、超薄金属薄膜和层状化合物的局部电子性质。在这项技术中，一个核心光电子和它的伴生俄歇电子被时间符合探测到。这种方法被用来探测具有高表面专一性的电子结构和研究氧化物表面极低的缺陷浓度。所研究的体系包括表面合金Ag/Cu(100)、Au/Ni(110)、Pd/Cu(100)和Ag/Pd(100)。表面原子混合在一起，尽管各组分在整体上是不相容的。分子吸附和表面缺陷之间的低维系统和相互作用也是感兴趣的。很大一部分工作是在布鲁克海文国家实验室的国家同步加速器光源进行的。这一研究项目本质上是跨学科的，涉及一名或多名博士后和研究生，他们接受了为在工业、政府实验室或学术界就业做准备的出色培训。这个实验研究项目涉及研究样品最外层原子层的先进方法。这类表面分析方法通常使用落在样品上的光束，这可能导致其他电子(S)和/或光被射出。在本工作中，探测到的粒子是一个电子和一个光子，它们在时间上是重合的，这表明它们都来自同一个原子事件。这种“俄歇-光电子符合谱(APECS)”方法被用于研究表面合金、超薄金属膜和层状化合物的局域电子性质。所研究的体系包括表面异质银/铜(100)、金/镍(110)、钯/铜(100)和银/钯(100)。表面原子混合在一起，尽管各组分在整体上是不相容的。分子吸附和表面缺陷之间的低维系统和相互作用也是感兴趣的。很大一部分工作是在布鲁克海文国家实验室的国家同步加速器光源进行的。这一研究项目本质上是跨学科的，涉及一名或多名博士后和研究生，他们接受了为在工业、政府实验室或学术界就业做准备的出色培训。***

w:\awards\awards96\*.doc 9801681 Bartynski This experimental research project is concerned with surface analysis using Auger-Photoelectron Coincidence Spectroscopy (APECS) focusing on local electronic properties of surface alloys, ultrathin metal films, and layered compounds. In this technique, a core photoelectron and its associated Auger electron are detected in time coincidence. This method is used to probe electronic structure with high surface specificity and to study extremely low defect concentrations on oxide surfaces. The systems under study include surface alloys Ag/Cu(100), Au/Ni(110), Pd/Cu(100 and Ag/Pd(100). The surface atoms intermix, even though the components are immiscible in the bulk. Low dimensional systems and interactions between molecular adsorbates and surface defects are also of interest. A large portion of the work is carried out at the National Synchrotron Light Source at Brookhaven National Laboratory. This research program is interdisciplinary in nature and involves one or more postdoctoral and graduate students, who receive excellent training in preparation for careers in industry, government laboratories or academia. %%% This experimental research project is concerned with advanced methods to study the outermost atomic layers of a sample. Such surface analysis methods typically employ a light (photon) beam falling on the sample, which can lead to other electron(s) and/or light being ejected. In the present work the detected particles are an electron and a photon, which are coincident in time, which is an indication that they both come from the same atomic event. This method of "Auger-Photoelectron Coincidence Spectroscopy (APECS)" is used to focus on local electronic properties of surface alloys, ultrathin metal films, and layered compounds. The systems under study include surface allo ys Ag/Cu(100), Au/Ni(110), Pd/Cu(100 and Ag/Pd(100). The surface atoms intermix, even though the components are immiscible in the bulk. Low dimensional systems and interactions between molecular adsorbates and surface defects are also of interest. A large portion of the work is carried out at the National Synchrotron Light Source at Brookhaven National Laboratory. This research program is interdisciplinary in nature and involves one or more postdoctoral and graduate students, who receive excellent training in preparation for careers in industry, government laboratories or academia. ***