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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Atomic displacements in BiFeO(3) as a function of temperature: neutron diffraction study.
A Palewicz1, R Przeniosło, I Sosnowska
1Institute of Experimental Physics, Warsaw University, Hoza 69 PL 00-681, Warsaw, Poland. radek@fuw.edu.pl
Acta Crystallographica. Section B, Structural Science
|July 21, 2007
Summary
High-resolution neutron powder diffraction reveals structural changes in bismuth ferrite (BiFeO(3)) near its Néel temperature. Key findings include structural distortions and anisotropic atomic vibrations impacting electric polarization.
Area of Science:
- Solid State Physics
- Materials Science
- Crystallography
Background:
- Bismuth ferrite (BiFeO(3)) is a multiferroic material with potential applications in various electronic devices.
- Understanding its crystal structure and phase transitions is crucial for optimizing its properties.
Purpose of the Study:
- To investigate the temperature-dependent crystal structure of BiFeO(3) using high-resolution neutron powder diffraction.
- To correlate structural parameters with the magnetic and electric properties of BiFeO(3) around its Néel temperature.
Main Methods:
- High-resolution neutron powder diffraction was employed to analyze the crystal structure of BiFeO(3).
- Measurements were conducted across a temperature range from 293 K to 923 K.
Main Results:
- A local minimum in the rhombohedral angle (alpha(rh)) was observed near the Néel temperature (T(N) ≈ 640 K).
- Gradual rotation of FeO(6) octahedra and an increasing Fe-O-Fe angle were noted with rising temperature.
- The displacement of Bi(3+) ions, influencing electric polarization, decreased with temperature.
- Anisotropic atomic vibrations of Bi(3+) and O(2-) ions were significant.
Conclusions:
- The study elucidates critical structural changes in BiFeO(3) associated with its magnetic ordering.
- These structural dynamics, particularly near T(N), provide insights into the interplay between structural, magnetic, and electric properties.
- Findings contribute to a deeper understanding of BiFeO(3) for advanced materials applications.
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