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Insights into cationic ordering in Re-based double perovskite oxides.
Tae-Won Lim1,2, Sung-Dae Kim2, Kil-Dong Sung2
1Department of Nano Science and Engineering, Kyungnam University, Changwon 631-701, Korea.
Scientific Reports
|January 26, 2016
Summary
Cationic ordering in strontium iron rhenium oxide (Sr2FeReO6) and strontium chromium rhenium oxide (Sr2CrReO6) impacts magnetic properties. Defect configuration, not just quantity, significantly influences magnetism.
Area of Science:
- Materials Science
- Solid State Chemistry
- Magnetism
Background:
- Cationic ordering in perovskite oxides influences their physical properties.
- Understanding defect structures is crucial for tuning material functionalities.
Purpose of the Study:
- To investigate the influence of cationic ordering on magnetic properties in Sr2FeReO6 (SFRO) and Sr2CrReO6 (SCRO).
- To differentiate the impact of defect structure on magnetic behavior.
Main Methods:
- Magnetic property measurements.
- Atomic-scale imaging techniques.
- First-principles calculations.
Main Results:
- Cationic ordering is sensitive to the host oxide, affecting SFRO and SCRO differently.
- Antisite (AS) defects exhibit distinct configurations: clustered in SFRO and scattered in SCRO.
- Clustered AS defects in SFRO more significantly degrade ferromagnetism compared to scattered defects in SCRO.
Conclusions:
- The nature and configuration of cationic ordering and antisite defects are critical for magnetic properties in these oxides.
- Defect structure plays a vital role in determining magnetic behavior beyond defect concentration.
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