ミックスバレンスの単分子磁石 (CpiPr5) の強制場は30Tを超えています
Hyunchul Kwon, K Randall McClain1, Jon G C Kragskow2
1US Navy, Naval Air Warfare Center, Weapons Division, Research Department, Chemistry Division, China Lake, California 93555, United States.
Journal of the American Chemical Society
|June 26, 2024
まとめ
新しいホルミウムとエルビウム複合体は独特の磁気特性を持ち,ホルミウム化合物は記録的な高強度を示し,高度な磁気材料への道を開く. この研究はランタニド基単分子磁石を研究しています
科学分野:
- 無機化学
- 材料科学
- マグネティズム
背景:
- Ln-Ln σ結合を持つ混合バレンスのディランタニド複合体は,高スピン基底状態と磁性アニソトロピーを示す.
- 以前の研究はGd,Tb,Dyに焦点を当て,TbとDyの変種において大きな磁気強制性を示した.
研究 の 目的:
- ホルミウム (Ho) とエルビウム (Er) のための新しい混合バレンスのディランタニド化合物 (CpiPr5) 2Ln2I3を合成し,特徴づけること.
- これらの新しい化合物の磁気阻害,緩やかな磁気放緩,強制力を含む磁気特性を調査する.
- ホー・コンプレックスとエール・コンプレックスとの間の異なる磁気行動の起源を理解する.
主な方法:
- 新しい混合バレンスのディランタニド複合体の合成: (CpiPr5) 2Ln2I3 (Ln = Ho, Er).
- 磁気感受性測定と変磁場研究を用いた特徴付け.
- 計算分析 (多構成計算) と遠赤外線磁光スペクトル検査
主要な成果:
- Ln-Ln結合を備えた最初の Ho と Er 分子化合物の合成に成功した.
- 両複合体は,スピン-スピン結合とLn-Ln結合電子により,高スピン基底状態を示す.
- ホルミウム複合体 (1-Ho) は28K未満の磁気阻害と556cm−1のスピン逆転バリアを示している.
- ホルミウム複合体は低温で記録的な強圧場 (> 32 T) を示しています.
- エルビウム複合体 (1-Er) は観測可能な磁気阻害または緩やかな磁気放緩を示さない.
結論:
- 新しい Ho と Er コンプレックスは,これらのランタニドの Ln-Ln 結合を持つ最初の分子化合物を表しています.
- 地元の磁性アニソトロピーの違いに関連して,HoとEr複合体の間の異なる磁性特性が観察される.
- ホルミウム複合体は,高い阻害温度と記録的な強制性により,単一分子磁石として例外的な可能性を示しています.
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