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Updated: Jun 30, 2026
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Nd(2) GaMnO(6) と La(2) GaMnO(6) のジャーン・テラー歪みによる磁気順序の制御
E J Cussen1, M J Rosseinsky, P D Battle
1Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK.
Journal of the American Chemical Society
|July 18, 2001
まとめ
LaMnO ((3)) とNdMnO ((3) のペロブスキットにおけるガリウムの置換は,結晶構造と磁気順序を変化させます. La(2) GaMnO(6) は,鉄磁石の絶縁体となり,Nd(2) GaMnO(6) は,Jahn-Tellerの歪みに対するGa(3+) の影響により,複雑な傾斜の反鉄磁性を表している.
科学分野:
- マテリアルサイエンス 材料科学
- 固体物理 固体物理学
- クリスタルグラフィーです.
背景:
- LaMnO ((3)) やNdMnO ((3) のようなペロブスキートマンガニットは,ヤーン・テラー歪みと反鉄磁性を表しています.
- カチオンの置換により,それらの構造的および磁性特性を大幅に調節することができます.
研究 の 目的:
- Ga (((3+) 置換によるLaMnO (((3) とNdMnO (((3) の結晶構造と磁性秩序への影響を調査する.
- フェロ磁性および傾斜反フェロ磁性装置を含む,その結果生じる磁気相を特徴付ける.
主な方法:
- 新しいペロブスキート相であるLa(2) GaMnO(6) とNd(2) GaMnO(6) の合成と特徴付け.
- 構造と磁気モメントの決定のための中性子粉の difraktion.
- マグネトメトリーは,キュリー温度やオーダーモントムなどの磁気特性を測定する.
主要な成果:
- La(2) GaMnO(6) は,フェロ磁気分離体 (T(c) = 70 K) として形成され,一貫したヤーン・テラー歪曲は抑制されているが,相関性のない歪曲は顕著である.
- Nd(2) GaMnO(6) は,Q(2) モードのヤーン-テラー歪みを持つペロブスキート構造を採用し,その大きさはGa(3+) により減少しています.
- Nd(2) GaMnO(6) は,フェロ磁性的に結合されたMn(3+) モメントと秩序付けられたNd(3+) モメントを持つ複雑な傾斜の反フェロ磁性構造を示しています.
結論:
- Ga (((3+) 置換は,これらのペロブスキートにおける結晶構造,ヤーン・テラー歪み,磁気秩序の相互作用に大きな影響を及ぼします.
- Ga(3+) の特異的な効果は,La(2) GaMnO(6) とNd(2) GaMnO(6) の間で異なっており,異なる磁気行動につながる.
- これらの構造-特性関係を理解することは,新しい磁気材料の設計に不可欠です.
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