多重ビスタビリティとトリスタビリティは,二重スピン状態変換で[Fe ((dpp)) ]2[Ni ((mnt)) ]2xMeNO2で [Fe ((dpp)) ]2[Ni ((mnt)) ]2に変換されます
Masayuki Nihei1, Hirotaka Tahira, Nobukazu Takahashi
1Graduate School of Pure and Applied Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8571, Japan.
Journal of the American Chemical Society
|February 18, 2010
まとめ
この研究は,複数のスピン状態変換を示す新しい鉄-ニッケル協調化合物を明らかにしています. 温度によって影響されるこれらのスピン移行には,鉄とニッケルの両方の成分が含まれ,異なる高温と低温の相につながります.
科学分野:
- 協調化化学について
- マテリアルサイエンス 材料科学
- 固体物理 固体物理学
背景:
- マルチコンポーネントシステムは,異なるイオンの相互作用によってユニークな特性を提供します.
- 移行金属複合体におけるスピン状態の移行は,高度な材料の開発に不可欠です.
- これらの移行を理解するには,詳細な構造的および磁気的特徴づけが必要です.
研究 の 目的:
- 鉄とニッケルを含む新しい多成分システムを合成し,特徴づけること.
- 温度に依存するスピン状態変換をカチオンの成分とアニオンの成分の両方で調査する.
- 異なる相に関連した構造および磁気特性を解明する.
主な方法:
- 変化温度X線構造分析. 変化温度X線構造分析.
- 磁気感受性の測定 磁気感受性の測定 磁気感受性の測定
- 熱容量測定 熱容量測定
- (57) Fe モスバウアー光譜法.
主要な成果:
- 合成された化合物 [Fe ((dpp) ((2))) [Ni ((mnt) ((2))) ] ((2)).MeNO ((2)) は複数のスピン状態変換を示しています.
- 高温相には,高スピン鉄とS=1/2.2のモノメリックニッケルが特徴です.
- 低温相では,低スピンの鉄と二磁性,二重化ニッケルが見られる.
- 中間相は,混合スピン状態と様々なニッケル二重化を示す.
- 5Kの鉄部で観測された光誘発スピン移行.
結論:
- 複数のコンポーネントのシステムは,温度によって引き起こされる複雑なスピン状態のダイナミクスを示しています.
- ニッケル二酸化を含む構造の変化は,スピン状態の移行と相関する.
- この化合物は,光に反応する磁気行動の可能性を示している.
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