Co-Ln混合金属フォスフォナートグリッドとケージは,分子磁気冷媒として使用されます
Yan-Zhen Zheng1, Marco Evangelisti, Floriana Tuna
1School of Chemistry, The University of Manchester, Oxford Road, M13 9PL, Manchester, United Kingdom.
Journal of the American Chemical Society
|December 17, 2011
まとめ
コバルト・ランタニド混合金属フォスフォナート複合体の6つのファミリーが合成され,研究されました. ガドリニウム誘導体は,ガドリニウム含有量に比例して,有意な磁熱効果を示した.
科学分野:
- マテリアルサイエンス 材料科学
- 無機化学 無機化学とは
- マグネティズム (磁気) とは
背景:
- コバルト・ランタニド混合金属フォスフォナートは,磁気性により興味を惹きます.
- 構造-性質の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.
研究 の 目的:
- コバルト・ランタニド混合金属フォスフォナート複合体の6つのファミリーを合成し,特徴づけること.
- 構造的多様性 (グリッドやケージ) と磁気特性について調査する.
- 磁熱効果 (MCE) を評価する.
主な方法:
- コバルト・ランタニド・フォスフォナート複合体の合成.
- X線微分法を用いた構造的特徴化.
- マグネトカロリック効果の測定を含む磁性特性測定.
主要な成果:
- 複合体の6つのファミリーが合成され,グリッドとケージ構造タイプに分けられました.
- 最大の磁熱効果は,ガドリニウム誘導体で観察されました.
- ガドリニウム誘導体のエントロピーの変化は,11.8から28.6 J kg ((-1) K ((-1) K) 3Kと7Tの範囲であった.
- MCEは,複合体のガドリニウム含有量と比例していることが判明しました.
結論:
- この研究では,さまざまな構造を持つ新しいコバルト・ランタニド・フォスフォナート複合体について報告しています.
- ガドリニウムベースの複合体は,有望な磁熱性特性を示しています.
- 観測されたMCEは,ガドリニウム比率と直接関係しており,磁気冷却材料の設計原理を提供します.
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