マングネス・ランタニド混合単分子磁石における磁化ヒステレスと量子トンネルの初期観測
Abhudaya Mishra1, Wolfgang Wernsdorfer, Khalil A Abboud
1Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, USA.
Journal of the American Chemical Society
|December 2, 2004
まとめ
研究者は,新しい混合移行金属/ランタニドクラスタを合成しました. ディスプロシウムを含むクラスターは,ヒステレスと量子トンネリングを含む単分子磁石の振る舞いを示す.
科学分野:
- 無機化学 無機化学とは
- マテリアルサイエンス 材料科学
- マグネチズム (磁気) とは
背景:
- 混合移行金属/ランタニドクラスターは,そのユニークな磁気特性により興味を惹きます.
- シングル分子磁石 (SMM) は,阻害温度以下で磁気ヒステレシスを示す分子化合物です.
研究 の 目的:
- 混合過渡金属/ランタニドクラスタの新しいファミリーを合成し,特徴づけること.
- これらの新しいクラスターの磁気特性を調査し,特にSMMの行動について調べる.
主な方法:
- マンガンのクラスター前駆体とランタニド窒素 (Nd, Gd, Dy, Ho, Eu) の反応.
- 結果となる[Mn11Ln4]45+コア複合体の結晶化と特徴付け.
- 磁気的振る舞いを探査するために,磁気感受性測定 (ACとDC) を行う.
主要な成果:
- [Mn11Ln4]45+コアを持つ混合3d/4fクラスターの新しいファミリーの合成が成功しました.
- ディスプロシウムを含む複合体は,SMM行動を示す,相外AC感受性信号を示した.
- 磁気化ヒステレスループと9.3KのエネルギーバリアがDy化合物で観察されました.
- 低温で温度に依存しないリラクゼーションの証拠は,磁気化の量子トンネル化を示唆しています.
結論:
- この研究で,初めて混合3d/4f単分子磁石がヒステレシスを示すことが報告されています.
- これらのシステムにおける磁気化の観測された量子トンネリングは,分子磁気の研究のための新しい道を開く.
- これらの発見は,高度な磁気材料の開発に寄与する.
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