デカコッパー (decacopper) の合成,構造,および鉄磁気的振る舞いは,p-tert-butylthiacalix[6]arene hexaanionicによってサポートされるクラスター複合体である
Takashi Kajiwara1, Noriyoshi Kon, Shuichi Yokozawa
1Department of Chemistry, Graduate School of Science, Tohoku University, Aramaki Aoba-ku, Sendai 980-8578, Japan. kajiwara@agnus.chem.tohoku.ac.jp
Journal of the American Chemical Society
|September 19, 2002
まとめ
私たちは,シアカリキサレンリガンドを使用して,新しいナノサイズのデカコッパー (decacopper) のクラスタを合成しました. この複合体は,銅イオンのユニークな配置により,フェロ磁気的行動を示す.
科学分野:
- 協調化化学について
- 超分子化学 超分子化学
- 材料科学 材料科学とは
背景:
- Thiacalixarenesは,金属イオンを調整する能力を持つ多用途のマクロサイクリックリガンドです.
- 特定の磁気特性を有する多核金属複合体の設計は,材料科学の重要な分野である.
研究 の 目的:
- 新しいナノサイズのデカコッパー (decacopper) のクラスター複合体を合成し,特徴づけること.
- 合成された銅クラスタの磁気特性を調査するために.
主な方法:
- p-tert-butylthiacalix[6]areneをリガンドとして使用したデカコッパー (decacopper) のクラスターの合成.
- 電気スプレー・イオン化質量スペクトロメトリー (ESI-MS) のようなテクニックを用いた構造的特徴付け.
- 温度依存磁気感受性測定 (chT) による磁気特性調査.
主要な成果:
- ナノサイズのデカコッパー (decacopper) のクラスター複合体が成功して合成されました.
- カリキサレンのリガンドは"絞った円"の形状を採用し,アンデカデントのリガンドとして作用した.
- ペンタコッパー (II) のサブユニットで構成されたクラスター・コアは,ヒドロキソとオキソグループで結びついているが,溶液では安定したままである.
- デカコッパー (decacopper) のクラスター・コア (cluster core) で,フェロマグネティックな行動が観察されました.
結論:
- 合成されたデカコッパー (decacopper) (II) クラスター複合体は安定しており,興味深い磁気特性を有しています.
- 観測された鉄磁気行動は,クラスター・コア内の銅 (II) イオン間の特定の電子相互作用から生じる.
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