Fundamental Aspects of Core Level Spectroscopies
In this chapter, we introduce some fundamental aspects of core level spectroscopies. The characteristics of core holes and core level spectroscopies will be given, and x-ray absorption and x-ray emission will be discussed on the basis of the interaction of x-rays with matter. We mainly confi ne ourselves to the one-electron approximation (the effect of electron-electron interactions on the core level spectroscopy will be discussed in detail from Chapters 3 to 8). At the end of the chapter, the x-ray and electron sources that are used for the core level spectroscopy are given.