Inelastic Electron Scattering and Spectroscopy

Abstract

Principles. This Chapter 4 first describes how high-energy electrons are scattered inelastically by materials, and then explains how electron energy-loss spectrometry (EELS) is used in materials research. Inelastic scattering occurs by the processes listed below in order of increasing energy loss, E. Energy is conserved in these inelastic processes-the spectrum of energy gains by the sample is mirrored in the spectrum of energy losses of the high-energy electrons. Electrons undergoing energy losses to crystal vibrations, quantized as phonons with E ∼ 10 −2 eV, are indistinguishable from elastically scattered electrons, given the present state-of-the-art for EELS in a TEM.