熱的に安定したテルビウム (II) とディスプロシウム (II) ビス-アミジナート複合物

Peng-Bo Jin¹, Qian-Cheng Luo¹, Gemma K Gransbury²

¹Frontier Institute of Science and Technology (FIST), State Key Laboratory of Electrical Insulation and Power Equipment, MOE Key Laboratory for Nonequilibrium Synthesis of Condensed Matter, Xi'an Key Laboratory of Electronic Devices and Materials Chemistry and School of Chemistry, Xi'an Jiaotong University, 99 Yanxiang Road, Xi'an, Shaanxi 710054, P. R. China.

Journal of the American Chemical Society

|November 24, 2023

まとめ

Tb (II) とDy (II) を含む新しい二価ランタニド (Ln) 複合体は,磁気逆転のための記録的な高エネルギーバリアを示し,単一分子磁気技術を進めている.

科学分野:

有機金属化学
無機化学
材料科学

背景:

ランタニド複合体は,その独特の磁気特性のために調査されています.
安定した二価ランタニド化合物の開発は困難です.
単分子磁石 (SMM) は,磁気逆転のために高エネルギーバリアを必要とします.

研究の目的:

新しい4座標の二価ランタニドビスアミディナート複合体を合成し,特徴づけます.
これらの複合体の電子構造と磁気特性を研究する.
単一分子磁石としての可能性を評価する

主な方法:

KC8によるランタニド (III) 前駆物質の減少
ハリド抽出は,シライライスされたヒドラジン塩を使用します.
X線微分法,光譜法 (NMR,EPR,UV対NIR,ATR-IR),ICP-MS,元素分析,およびSQUID磁気測定による特徴付け
ab initio CASSCF-SO計算を用いた計算分析

主要な成果:

[Ln(Piso) 2 (Ln = Tb, Dy) を二価ランタニド中心と4fn5d1構成で成功して合成した.
座標幾何学は正方形の平面と四面体との間にあり,強い軸性リガンドフィールドがある.
磁気逆転に対する記録的なエネルギーバリア: Tb (II) の1920 K,Dy (II) の1964 K.
横断フィールドと状態の混合に起因する,急速なゼロフィールドの磁気放緩を観測した.

結論:

合成された二価ランタニドビス-アミジナート複合体は,SMMにおける重要な進歩を表しています.
観測された高エネルギーバリアは,これらの化合物の磁気メモリアプリケーションの可能性を強調しています.
磁気放松メカニズムに関するさらなる調査が必要である.

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