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Updated: May 9, 2026

Picometer-Precision Atomic Position Tracking through Electron Microscopy
Published on: July 3, 2021
Direct observation of cationic ordering in double perovskite Sr₂FeReO₆ crystals
Si-Young Choi1, Jong Bong Lim, Yuichi Ikuhara
1Advanced Characterization and Analysis Group, Korea Institute of Materials Science, Changwon 641-831, Republic of Korea. youngchoi@kims.re.kr
Abstract:
Two kinds of Sr₂FeReO₆ (SFRO) samples, pristine SFRO and Re-excess SFRO, were prepared and we visualized the local atomic structure in terms of cationic ordering in the prepared SFRO samples via high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM). HAADF-STEM results demonstrated the high degree of cationic ordering maintains in both the pristine SFRO and Re-excess SFRO samples. On the other hand, defective structures such as antiphase boundary and Re-deficient phase were observed dominantly in the pristine SFRO, and thus the poor magnetic property in the pristine SFRO is attributed to those defective structures related with the frustrated Fe/Re ordering.
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