An X-ray absorption spectroscopic study of the metal site preference in Al1−xGaxFeO3

Magnetoelectric materials have potential for being introduced into next generation technologies, especially memory devices. The AFeO3 (Pna21; A=Al, Ga) system has received attention to better understand the origins of magnetoelectric coupling. The magnetoelectric properties this system exhibits depend on the amount of anti-site disorder present, which is affected by the composition and the method of synthesis. In this study, Al1−xGaxFeO3 was synthesized by the ceramic method and studied by X-ray absorption spectroscopy. Al L2,3-, Ga K-, and Fe K-edge spectra were collected to examine how the average metal coordination number changes with composition. Examination of XANES spectra from Al1−xGaxFeO3 indicate that with increasing Ga content, Al increasingly occupies octahedral sites while Ga displays a preference for occupying the tetrahedral site. The Fe K-edge spectra indicate that more Fe is present in the tetrahedral site in AlFeO3 than in GaFeO3, implying more anti-site disorder is present in AlFeO3.

Al1−xGaxFeO3 has been investigated by XANES. Through examination of Al L2,3-, Ga K-, and Fe K-edge XANES spectra, it was found that more anti-site disorder of the Fe atoms is present in AlFeO3 compared to in GaFeO3.Figure optionsDownload as PowerPoint slideHighlights
► Al1−xGaxFeO3 was investigated by X-ray absorption spectroscopy.
► Ga prefers to occupy the tetrahedral site in Al1−xGaxFeO3.
► Fe prefers to occupy the octahedral sites in Al1−xGaxFeO3 as x increases.
► More anti-site disorder is present in AlFeO3 compared to in GaFeO3.