A {Gd12Na6} 低磁場および低温で磁熱効果を記録した分子四重車
Thomais G Tziotzi1, David Gracia2, Scott J Dalgarno3
1Department of Chemistry, University of Crete, Voutes 71003, Herakleion, Greece.
Journal of the American Chemical Society
|April 3, 2023
まとめ
研究者は新しいガドリニウム基化合物を合成し, 記録的な磁熱効果を示した. この材料は低温と磁場での効率的な磁気冷却の可能性を示しています.
科学分野:
- 無機化学
- 材料科学
- マグネティズム
背景:
- ランタニドベースの化合物は,そのユニークな磁気特性のために調査されています.
- マグネトカロリック効果 (MCE) は,先進的な冷却技術の開発に不可欠です.
- 低温で有意なMCEを持つ分子磁石を設計することは依然として課題です.
研究 の 目的:
- 新しい多核ガドリニウム-ナトリウム複合体を合成し,特徴づけること.
- 合成された化合物の磁気特性と磁熱効果を調査する.
- 低磁場での分子物質における磁熱効果の新記録を確立する.
主な方法:
- ガドリニウムアセテート,サリチアルデヒド,およびメトキシドナトリウムの溶媒補助反応.
- 四輪複合体の構造的決定のための単一結晶X線 difraktion.
- 磁気相互作用と磁熱効果を分析するための磁気感受性測定.
主要な成果:
- 新型四輪複合体[Gd12Na6(OAc) 25(HCO2) 5(CO3) 6(H2O) 12·9H2O·0.5MeCNが成功して合成されました.
- 結晶構造は,{Gd6}と{Na3}のリングでGdIIIとNa+イオンのユニークな配置を示しています.
- GdIIIイオンの間の弱い反鉄磁気相互作用が観察され,1Tと0. 5Kでの記録的なMCEは−ΔSm=29. 3 J kg−1であった.
結論:
- 合成されたGd-Na複合体は 特殊な磁熱特性を示しています
- この化合物は低磁場冷却における 分子材料の新しい基準を設定します
- この発見は,効率的な磁気冷却のための複雑な多核構造の設計の可能性を強調しています.
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