Bismuth Ferrite Temperature-Dependent Electron Density Map and Pair Distribution Function study in correlation with magnetic phase transitions

Document Type : Original Article

Authors

1 Physics Department, Faculty of Basic Sciences, German University in Cairo, Cairo, Egypt

2 X-Ray Crystallography Lab., Solid State Physics Department, National Research Centre, Giza, Egypt

3 Physics Department, Faculty of Science, Helwan University, Cairo, Egypt

4 Helwan University

Abstract

Bismuth ferrite (BiFeO3, or BFO) is a multiferroic material exhibiting both ferroelectric and antiferromagnetic properties, making it a subject of intense research. This study investigates the temperature-dependent behavior of BiFeO₃'s average and local structural parameters, along with electron density maps, with a specific focus on the Néel temperature (TN ~ 623–643 K). High-resolution X-ray diffraction (XRD) was employed as a cost-effective and conventional method to explore potential magnetic phase transitions as well as the coupling between electronic structure and magnetic properties in BiFeO₃. Rietveld refinement was used to extract average structural parameters and generate two-dimensional electron density maps (EDM), while the reduced pair distribution function G(r) was analyzed to study local structural parameters. Although no significant anomalies were observed in XRD patterns or structural parameters, EDM revealed notable variations in electron density around Néel temperature. These findings enhance our understanding of the interaction between electronic and magnetic properties in BiFeO₃ and emphasize the necessity of advanced techniques to improve data resolution and accuracy for future studies.

Keywords