3次元シアン化物橋渡しバイメタリック磁石の圧力反応
Masaaki Ohba1, Wakako Kaneko, Susumu Kitagawa
1Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan. ohba@sbchem.kyoto-u.ac.jp
Journal of the American Chemical Society
|March 12, 2008
まとめ
圧力は,シアン化物橋渡しコーディネーションポリマーの磁気特性を大幅に変化させます. これらの材料は,磁気相の可逆的および不可逆的な変化と,水立圧下での移行温度を示し,フレームワークの強さと磁気構造の洞察を明らかにします.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- マグネチズム (磁気) とは
背景:
- シアン化物橋渡しバイメタリックコーディネーションポリマーは,調節可能な磁気特性を有する材料のクラスです.
- 圧力などの外部刺激に対するこれらの材料の反応を理解することは,先進技術におけるそれらの応用にとって極めて重要です.
研究 の 目的:
- 3つの異なる3Dシアン化物橋渡しバイメタリック協調ポリマー磁石の構造および磁気特性に対する水静圧の影響を調査する.
- 圧力による変化と,これらの材料の固有の磁気構造とフレームワークの安定性を相関させる.
主な方法:
- ピストン・シリンダーとダイヤモンド・アンビル・セルを使用して,最大19.8GPaまでの水圧を体系的に適用する.
- 異なる圧力条件下における構造的および磁気的相変化の特徴.
- 移行温度 (TC) と磁化を含む磁性特性の分析.
主要な成果:
- フェリマグネット [Mn(en) ]3[Cr(CN) [6]2.4H2O (1) は,可逆性のある結晶から形無形のような相移行を示し,TCは4.7GPaで69Kから126Kに増加し,高圧では磁気化の抑制を示した.
- 鉄磁石 [Ni(dipn) ]3[Cr(CN) [6]2.3H2O (2) は,結晶性を保持しながら,4.7GPaまでの可逆的な鉄磁石からパラ磁石のような相変換を示しました.
- 毛細な鉄磁石 [Ni(dipn) ]2[Ni(dipn) ((H2O) ]][Fe(CN) [6]2.11H2O (3) は容易に無形化し,不可逆的にその鉄磁気相を1.0 GPa以下で失いました.
結論:
- 柔軟なシアン化物橋渡しの磁気フレームワークは,磁気構造とフレームワークの頑丈さの変動を反映して,大きな圧力感度を示します.
- 観測された圧力誘発変換は,これらの協調ポリマーの機械的および磁気的振る舞いのGPaスケールの理解を提供します.
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