鉄と反鉄磁気結合スイッチは,銅 (II) と窒素酸化物コーディネーションボンドの周りの回転変形に伴います
Atsushi Okazawa1, Daisuke Hashizume, Takayuki Ishida
1Department of Applied Physics and Chemistry, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan.
Journal of the American Chemical Society
|July 31, 2010
まとめ
2つの新しい銅 (II) 複合体は,異なる磁気行動を示す. 1つは一貫した鉄磁気結合を示し,もう1つはフェーズ移行を経て,鉄磁気から反鉄磁気相互作用に切り替え,スピンシステムを理解するために不可欠です.
科学分野:
- 協調化化学について
- マグネト化学 マグネト化学
- マテリアルサイエンス 材料科学
背景:
- 銅 (((II) 複合体と窒素酸化リガンドは,磁気特性のために興味があります.
- 構造と磁気結合の関係を理解することは,分子磁石の設計の鍵です.
研究 の 目的:
- 新型銅 (((II) コンプレックスとテルトブチル2ピリジル窒酸化物 (2pyNO) を合成し,構造的に特徴づけること.
- これらの複合体の磁気特性と相変遷を調査する.
主な方法:
- 銅 (II) 複合体の合成と構造的特徴.
- 単一結晶X線微分分析. 単一結晶X線微分分析. 単一結晶X線微分分析. 単一結晶X線微分分析.
- 温度変数磁気感受性の測定. 温度変数磁気感受性の測定.
主要な成果:
- 2つの同型銅 (((II) 複合体, [Cu (((2+)) (((2pyNO (((-)))) (((2pyNO (((*)))))) (((2) (((BF (((4))) (((2) (1 x BF (((4)) と [Cu (((2+)) (((2pyNO ((-)) (((2pyNO (((*)))))) (((2) (((ClO (((4))) (((2) (1 x ClO (((4)),が製造されました.
- 複合体はジグザグ型の線形スピンシステムを4つのパラマグネティックS = 1/2センターで特徴付けています.
- 1 x ClO ((4) は,鉄磁性銅根結合を示し,1 x BF ((4) は,64 Kの構造的相変化を示し,鉄磁性結合から反鉄磁性結合への移行を示した.
結論:
- 磁気的行動は,コントラニオンと微妙な構造変化に強く依存しています.
- 銅のdシグマと窒素酸化物のpi*軌道の直角的配置は,鉄磁気結合に極めて重要です.
- 構造的相変遷は,これらのシステムの磁気相互作用を大幅に変化させることができます.
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