2.6.6 The use of different interactions in XRS
Spectroscopy is the study of physical systems by the electromagnetic radiation with which they interact or that they produce. Spectrometry is the measurement of such radiations as a means of obtaining information about the systems and their components. In certain types of spectroscopy, the radiation originates from an external source and is modified by the system, whereas in other types, the radiation originates within the system itself.
The mechanisms of interactions of x-rays with matter are used for implementing different X-ray Spectroscopy techniques:
Ionization (either with photons or charged particles) is used to produce x-ray characteristic emission, which is the basis for x-ray emission spectroscopy techniques, including XRF, PIXE, SEM-EDS and Synchrotron XRF.
Photoelectric absorption is used in a number of x-ray absorption spectroscopy techniques for determining the local geometric, the electronic structure of matter and to gather information on the atoms electron binding. Absorption spectroscopy also includes Extended X-Ray Absorption Fine Structure (EXAFS) and X-ray Absorption Near Edge Structure (XANES).
Scattering is the basis of non-destructive analytical techniques which reveal information about the crystalline structure, chemical composition, and physical properties of materials and thin films.
X-ray diffraction reveals information on the atomic and molecular structure of crystals and periodic arrangements of atoms.
A brief overview of XRS emission techniques and methodologies is provided in section 5 of this course.