マンガンの棒の一族:合成,構造,磁気特性
Gopalan Rajaraman1, Muralee Murugesu, E Carolina Sañudo
1Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.
Journal of the American Chemical Society
|November 26, 2004
まとめ
新しいマンガン複合体が合成され,特徴づけられました. 複合体1は単一分子磁石の振る舞いを示し,高度な磁気応用の可能性を示しています.
科学分野:
- 無機化学 無機化学とは
- 材料科学 材料科学とは
- マグネト化学 マグネト化学
背景:
- 混合価金属三角形は,新しい磁気材料の先駆体である.
- 1,1,1-tris (((hydroxymethyl) ethane (H(3) thme) と1,1,1-tris (((hydroxymethyl) propane (H(3) tmp) のような三足体結合体は,複雑な構造を形成することができる.
研究 の 目的:
- 新しいマンガンの棒のような複合体を合成し,特徴づけること.
- グラウンドステート・スピンと磁気行動を含む,これらの複合体の磁気特性を調査する.
主な方法:
- アセトニトリルにおける三脚リガンドと混合価マンガンの三角形の反応.
- 変数温度直流 (dc) の磁気感受性測定. 磁気感受性の測定. 磁気感受性の測定. 磁気感受性の測定.
- 密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.密度関数理論 (DFT) の計算.
- 単結晶ヒステレスループとリラックス測定.
主要な成果:
- 縁を共有する三角形から派生したマンガンの棒のような複合体の家族が合成されました.
- 複合体1 ([Mn(12) O(4) ((OH) ((2) ((PhCOO) ((12) ((thme) ((4) ((py) ((2))) は,S = 7の基本状態を示し,単一分子磁石 (SMM) の行動を示しています.
- 複合体2 ([Mn(8) O(4) (((CH(3)) (((3) CCO(2)) (((10) ((thme) (((2) (((py) ((2))) は,S = 6の基底状態を有する.
- 複合体3 ([Mn{7) O{2}{PhCO{2}{9}{thme}{2}{py}{3}) は,S=7の基底状態を有する.
- 複合体4 ([Mn(6) ((((CH(3)) (((3) CCO(2))) ((8) (((tmp) (((2) (((py) ((2))) は,フィットされたS = 3の基底状態を持ち,DFTはS = 4を示唆しています.
- 複合体5 ([Mn(6) ((CH(3) CO(2)) ((6) ((thme)) ((2) ((H(2) tea) ((2))) は満足のいくフィットを示せず,DFTはS = 0.0を示唆しています.
結論:
- 合成されたマンガン複合体は,多様な磁気特性を示しています.
- 複合体1は単一分子磁石として識別され,分子磁気性の可能性を強調しています.
- 構造的および磁性特性は,リガンドの選択と金属クラスター構造によって影響を受けます.
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