固体相における分子間陽子伝達:水素からオキシブリッジされた鉄から結晶から結晶への変容の希少な例 ((III) 分子ベースの磁石
Donatella Armentano1, Giovanni De Munno, Teresa F Mastropietro
1Dipartimento di Chimica, Università della Calabria, via P. Bucci, 87036 Rende, Cosenza, Italy.
Journal of the American Chemical Society
|August 4, 2005
まとめ
新しい鉄 (III) 化合物は,固体相において分子間陽子の移転を経て,ヒドロキソブリッジをオキソブリッジに変換する. この構造の変化の結果,結晶状の材料は,70Kの磁気配列を示しています.
科学分野:
- 無機化学 無機化学とは
- 固体化学 固体化学
- マテリアルサイエンス 材料科学
背景:
- 鉄 (III) 化合物は,様々な構造的モチーフと磁気特性で知られている.
- 固体無機化合物における陽子伝達反応は,反応性や相変遷を理解するために極めて重要です.
- この研究は,興味深い磁気行動の可能性のある新しいム-ヒドロキソ鉄 (III) 複合体に焦点を当てています.
研究 の 目的:
- 新しいム-ヒドロキソ鉄 (III) 化合物を合成し,特徴づけること.
- 固体相における分子間陽子伝達の発生と結果を調査する.
- 磁気特性を探求し,結果として生じる材料の順序を決定する.
主な方法:
- {EtNH3[Fe2(ox) 2Cl2(mu-OH) ]].2H2O}n化合物の合成について
- 陽子移動前と後の固体構造を決定するX線結晶学.
- 磁気オーダリングを調査するための磁気感受性測定.
主要な成果:
- 新しいム-ヒドロキソ鉄 (III) 化合物が成功裏に合成され,特徴づけられました.
- ヒドロキソブリッジから水分子への分子間陽子の移転は,固体状態で観察されました.
- 陽子の移転により,ム-ヒドロキソブリッジの代わりにム-オクソブリッジを持つ結晶化合物が形成されました.
- 最初の結晶形と最後の結晶形は,スピン・カンティングにより,約70Kで磁気オーダーリングを示す.
結論:
- 固体相の分子間陽子転送は,協調化合物の構造変化につながる可能性があります.
- 観測された変換により,安定した結晶型のムオキシ鉄 (III) 化合物が得られます.
- これらの化合物の磁気順序は,比較的高い温度で発生するスピン・カンティングに起因する.
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