Chemical state analysis is quite important in X‐ray photoelectron spectroscopy. Auger parameter analysis is one of the useful methods to analyze the chemical state in X‐ray photoelectron spectroscopy, because it is not necessary to take the charging effect into account for the analysis of nonconductive materials, especially for the simple material systems of a single chemical state. For the analysis of complicated complex systems, here, we developed the Auger parameter analysis combined with the curve fitting calculation using standard Auger spectra. Copper oxide complexes consisting of a mixture of CuO and Cu2O oxide states were formed on copper platelets by annealing in atmospheric ambient. For those samples, by combining the curve fitting using standard Cu, CuO, and Cu2O Auger spectra, two oxide states were clearly distinguished in the Auger parameter analysis. Thus, this advanced Auger parameter analysis is believed to be promising for the chemical state analysis of complicated complex systems.
The Ka satellite or shake-off lines can be observed by wavelength-dispersive spectrometry on the highenergy side of the main Ka peak. Occasionally, chemical state analysis of an emitting atom has been attempted using the shape and position of these lines. Recent extensive theory and experiment have shown that it is fruitful to take a similar approach using extended x-ray emission fine structure (EXEFS) arising from the radiative Auger effect (RAE). This fine structure is found in a low-intensity spectrum on the low-energy side of the Ka peak.We have studied the RAE spectra of the Ka lines of the elements F through to Ca by EPMA. The RAE peaks have energies close to the KLL energies of Auger transitions. In the lighter elements in this series, it was found that the difference between Ka and the RAE peak energies becomes quite small. For elements lighter than fluorine, it is difficult to observe the RAE peaks because they are overlapped by the main Ka line. At the higher energy end of the series, the intensity of the RAE lines becomes very small. The utility of the RAE lines for state analysis is limited, in practice, to the elements F through to Ca. The extended x-ray emission fine structure (EXEFS) of the RAE spectra has been used to calculate local bonding parameters.Both shake-off and RAE spectra associated with the F Ka line have been studied experimentally in the rare earth fluorides. The KLL RAE moves to lower energy as the atomic number of the rare earth cation increases. This has been confirmed theoretically by calculating electron energies using discrete variational Xa molecular orbital theory. The shake-off peaks increase in intensity relative to the main Ka peak because atomic number increases, contrary to expectation. It is considered that this could be due to temporary covalency. The EXEFS of the RAE spectra has been used to calculate local bonding parameters.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.