テクネチウム酸化物における反鉄磁気性. CaTcO3の構造について
Maxim Avdeev1, Gordon J Thorogood, Melody L Carter
1Bragg Institute, Australian Nuclear Science and Technology Organisation, Private Mail Bag 1, Menai, NSW 2234 Australia.
Journal of the American Chemical Society
|January 28, 2011
まとめ
カルシウムテクネチウム酸化物 (CaTcO3) ペロブスキットは,高ニール温度800Kで反鉄磁性を表します.この磁気移行は構造の変化なしに起こりますが,有意な磁気圧縮を示します.
科学分野:
- 固体化学 固体化学
- 材料科学 材料科学とは
- マグネティズム (磁気) とは
背景:
- ペロブスキート酸化物は,多様な電子および磁気特性を有する多用途の材料です.
- テクネチウム基化合物は,テクネチウムイソトープの放射性のため,あまり研究されていない.
研究 の 目的:
- 新型テクネチウムペロブスキート (CaTcO3.3) を合成し,特徴づけること.
- CaTcO3.3の磁気および構造的性質を調査する.
主な方法:
- CaTcO3.3の合成について
- 構造分析のためのシンクロトロンX線と中性子 difraktionの組み合わせ.
- マグネティックプロパティの測定.
- 電子的な構造計算.
主要な成果:
- CaTcO3.3の合成が成功しました.
- CaTcO3は,約800 Kの高いニール温度 (TN) の抗鉄磁性を示す.
- 磁気変遷は構造的相変遷を伴わない.
- 磁気状態に入ると有意な磁気圧縮が観察されました.
- 実験結果は,理論的な電子構造計算と一致しています.
結論:
- CaTcO3は,非常に高いニール温度を持つ新しい反鉄磁性ペロブスキートです.
- 磁気移行中の構造変化の欠如と磁気圧縮の存在は,この材料のスピン・ラットレス結合に関する洞察を提供します.
- 電子構造の計算は,観測された磁気行動をサポートします.
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