Auger-Photoelectron Coincidence Studies of Solids and Their Surfaces

9411610 Bartynski将利用同步辐射俄歇-光电子符合谱技术研究选定的金属、半导体和氧化物的核能级线形和俄歇电子能谱。APECS的灵敏度增强将被用来研究清洁和吸附覆盖表面的核心能级移动、电荷转移和电子结构。利用APECS消除寿命展宽的能力，我们将探索几种3D(4D)过渡金属中3P(4P)核能级的线形，以进行表面位移和隐藏分裂。还将通过测量核价(CVV)俄歇跃迁与移动的核能级的一致性来研究非均匀固体中特定位置的电子性质和关联效应。最后，我们将利用APECS的独特功能来探索光激发/衰变过程本身。大部分研究将在布鲁克海文国家实验室的国家同步辐射光源进行。我们小组利用同步辐射作为一种新的固体实验探头，发展了俄歇-光电子符合谱。这比传统的俄歇电子或光电子能谱有了质的改进。它具有更高的表面灵敏度，消除了背景信号，锐化了谱线，为研究复杂体系的局域电子性质提供了一种新的、独特的方法。这项技术将被用来获得关于清洁和吸附覆盖的半导体和金属表面的电子结构和成键的新信息。这项技术的特殊性质将被用来探测固体化合物中不同原子的电子性质。更清晰的谱线将为研究固体中的磁效应和电子相互作用提供新的方法。最后，这项技术的独特能力将为光激发/衰变过程本身提供线索。大部分研究将在布鲁克海文国家实验室的国家同步辐射光源中进行。***

9411610 Bartynski A technique of Auger-photoelectron coincidence spectroscopy (APECS) with synchrotron radiation will be employed to study the core level line shapes and Auger electron spectra in selected metals, semiconductors and oxides. The enhanced sensitivity of APECS will be used to study the core level shifts, charge transfer, and electronic structure at the clean and adsorbate covered surfaces. With the ability of APECS to eliminate lifetime broadening, we will probe the line shapes of 3p (4p) core levels in several 3d (4d) transition metals for surface shifts and hidden splittings. Site- specific electronic properties and correlation effects in inhomogeneous solids will also be studied by measuring core-valence (CVV) Auger transitions coincidence with shifted core levels. Finally, we will use the unique capabilities of APECS to explore the photoexcitation/decay process itself. The majority of the research will be performed at the National Synchrotron Light Source of Brookhaven National Laboratory. Our group has developed Auger-photoelectron coincidence spectroscopy using synchrotron radiation as a new experimental probe of solids. This is a qualitative improvement over conventional Auger electron or photoelectron spectroscopy. It is more surface sensitive, it eliminates background signal, it sharpens spectral lines, and it provides a new and unique way to study the local electronic properties of complicated systems. The technique will be utilized to obtain new information about the electronic structure and bonding at clean and adsorbate covered semiconductor and metal surfaces. The site-specific nature of the technique will be used to probe the electronic properties of different atoms in solid compounds. The sharper spectral lines will allow new ways to investigate magnetic effects and electronic interactions in solids. Finally the unique capabilities of this technique will provide clues to the photoexcitation/decay process itself. The ma jority of the research will be performed at the National Synchrotron Light Source of Brookhaven National Laboratory. ***