単分子磁石としての二座標複合体
Xiao-Nan Yao1, Jing-Zhen Du2, Yi-Quan Zhang3
1Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, PR China.
Journal of the American Chemical Society
|December 13, 2016
まとめ
新しいコバルトイミド複合体は,単分子磁石 (SMM) として記録的な性能を達成します. これらの分子は緩やかな磁気放緩を示し,高度な分子磁気の応用への道を開きます.
科学分野:
- 分子磁気
- 協調化学
- 量子材料について
背景:
- 強化された磁性アニソトロピーを持つ単分子磁石 (SMM) の開発は,分子磁性の進歩に不可欠である.
- 高性能のSMMは,磁性アニソトロピーを増加させる新しい分子設計を必要とします.
研究 の 目的:
- 高性能SMMアプリケーションのための新しい2座標コバルトイミド複合体の設計と合成.
- これらのコバルト複合体の大きな磁性アニソトロピーの起源を調査する.
主な方法:
- 2座標のコバルトイミド複合体の合成
- マグネチゼーション・リラクゼーションの測定は,ゼロの直流フィールド下で行われます.
- シングルイオンとCo-Nカップリングモデルを用いた理論的調査.
主要な成果:
- 報告されたコバルトイミド複合体は,ゼロフィールドでの磁気化の緩やかな緩和を示しています.
- トランジション・メタルベースのSMMでは,413cm-1の記録的な高効率リラクゼーションバリアを達成した.
- 理論的なモデルは,磁性アニソトロピーの強化における擬似線形リガンドフィールドと強いCo-Nフェロ磁性相互作用の役割を明らかにした.
結論:
- 2座標のコバルトイミド複合体は,高性能SMMのための有望なプラットフォームです.
- [CoN]+コアの固有の大磁性アニソトロピー,特に MJ = ± 7/2 グラウンド・クレイマーズ・ダブルレットは,それらの SMM 行動の鍵です.
- この研究は,移行金属ベースのSMMの新しい基準を設定し,将来の分子設計を導く.
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