Category:XAS

X-ray absorption spectroscopy (XAS) comes in many flavors. One of the most important is X-ray absorption near-edge spectroscopy (XANES). XANES is a very strong (and experimentally heavily used) method for the characterization of materials. The simulation involves the excitation of a core electron into valence/conduction bands. Since the electron stays strongly localized on the atom for most semiconductors and insulators, the inclusion of electron-hole interactions in the calculations is absolutely crucial. Two methods are mainly used:

• Supercell core-hole theory ^[1].
• Bethe-Salpeter equation (BSE) method.

To get familiarized with XAS or XANES calculations one should read the theory behind the method and do the following tutorial: XAS - Tutorial. The how to gives an overview of the steps needed to perform XAS calculations within the super cell.

Theoretical background

• Theoretical backroung for XAS calculations: XAS theory.

How to

• XAS (XANES) spectra from the super-cell core-hole method: SCH calculations.

Tutorial

• Tutorial to perform XAS calculations: XAS - Tutorial.