48 Kで磁気ヒステリースを示すビスモノフォソリルジプロシウムカチオン
Peter Evans1, Daniel Reta1, George F S Whitehead1
1Department of Chemistry, School of Natural Sciences , The University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom.
Journal of the American Chemical Society
|November 22, 2019
まとめ
研究者らは,フォスフォリル環を用いた新しいディスプロシウム単分子磁石 (SMM) を開発した. このSMMは,より高い温度で磁気メモリを示し,データ保存の可能性を向上させます.
科学分野:
- 協調化学
- 材料科学
- 量子コンピューティング
背景:
- 単分子磁石 (SMM) は,高密度データストレージに不可欠です.
- ランタニドサンドイッチ複合体は,77Kの磁気記憶を示し,SMM候補として有望である.
- これらのSMMのリラックスメカニズム,特にアロマティックリングを含むものは,さらなる解明を必要とします.
研究 の 目的:
- 新型ビスモノフォシルディスプロシウムSMMの合成と特徴づけ
- 磁気リラックスダイナミクスを調査し,その背後にあるメカニズムを理解する.
- 将来の開発のためにランタニドSMMにおける放松過程の理解を精進する.
主な方法:
- ディスプロシウムSMMの合成, [Dy(Dtp) 2][Al{OC(CF3) 3}4 (1).
- SQUID マグネトメトリーは,逆転バリアやヒステレスなどの磁気特性を決定します.
- スピンのダイナミクスとリラクゼーション経路を分析する Ab initio 計算.
主要な成果:
- 化合物1は,1760 Kの磁気化逆転と48 Kまでの磁気ヒステリシスの有効な障壁を示しています.
- Ab initio計算では,既知のディスプロソセニウムSMMと比較して,基底状態への移行が遅いことが示されています.
- 複合体1における全体的なより速い放松は,圧縮された電子エネルギーと共振振動モードに起因する.
結論:
- この研究は,bis-C5/C4PサンドイッチランタニドSMMにおけるリラックスプロセスに関する洞察を提供します.
- これらのメカニズムを理解することは,より高いブロック温度を持つSMMを合理的に設計する鍵です.
- この研究は,データストレージアプリケーションのための高度な磁気材料の開発に寄与します.
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