XPS Insight Note: Coster–Kronig Broadening

Abstract

Inconsistent peak broadening of doublet peaks in X-ray photoelectron spectroscopy is commonly observed for many transition metals, lanthanides and actinides, which may complicate peak fitting—especially for newer practitioners. In this insight note, we discuss why this broadening occurs, what governs the degree of broadening and how analysts and spectroscopists can account for this in their modelling.