核磁共振構造探査機としてのランタニド複合体:シフト反応剤アドゥクトのパラマグネティックアニソトロピー
Science (New York, N.Y.)
|September 15, 1972
まとめ
ランタニドシフト反応剤の磁性アニソトロピーは,有意な非軸性感受性テンサーを明らかにする. これらの固体状態の発見は,溶液ベースの核磁気共鳴 (NMR) のシフトデータとよく一致しています.
科学分野:
- 協調化化学について
- 固体物理 固体物理学
- 核磁共振スペクトロスコーピー 核磁共振スペクトロスコーピー
背景:
- ランタニドシフト反応剤 (LSR) は,複雑なNMRスペクトルを簡素化するために不可欠です.
- LSRアダクトの磁性特性を理解することは,その応用の鍵です.
- 以前の研究は,限られた固体データで,溶液状態の行動に焦点を当てていました.
研究 の 目的:
- パラマグネティック8座標ランタニドシフト反応剤アドクトの単結晶の磁性アニソトロピーを調査する.
- 固体磁気データを溶液状態核磁気共鳴 (NMR) のシフト結果と比較する.
- これらのランタナイド複合体における結晶構造と磁気行動の関係を解明する.
主な方法:
- 磁性アニソトロピーの測定は,ランタナイド複合体の単一結晶で行われた.
- 研究された複合体は,特定の有機結合体を持つ8座標ランタニドイオンの添加物を含んでいた.
- ランタニドスが調査した: Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb.
主要な成果:
- すべての測定されたランタニドアドクトの感受性テンソーは,高度にアニゾトロプ的で非軸性であることが判明しました.
- ランタナイド系全体で有意な磁性アニソトロピーが観察されました.
- 固体状態データから計算された二極核磁気共振シフトは,溶液結果と良好な一致を示した.
結論:
- これらのランタニドシフト反応剤添加物の固体磁性アニソトロピーは,実質的で非軸性である.
- 固体と溶液のNMRシフトデータとの一致は,スペクトル行動を予測する際に磁気アニソトロピーの使用を検証します.
- これらの発見は,ランタナイドの協調化学と磁気特性の理解を深める.
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