{Fe(9-x) Co(x) [W(CN) ]6} (x = 0-9) の分子固体溶液における電荷移転補助相変化と緩やかな磁気リラックス機能の調節
Szymon Chorazy1,2, Jan J Stanek3, Wojciech Nogaś1
1Faculty of Chemistry, Jagiellonian University , Ingardena 3, 30-060 Kraków, Poland.
Journal of the American Chemical Society
|January 14, 2016
まとめ
この研究は,調整可能な磁気特性を有する新しい鉄・コバルト・tungstenクラスタを合成します. 鉄とコバルトイオンの比率は,電荷の移転,相変化,磁気放緩を制御し,材料の機能を正確に制御します.
科学分野:
- 無機化学
- 材料科学
- マグネト化学
背景:
- サイアニド・ブリッジ・コーディネーション・コンポーネントは 調節可能な電子と磁気特性を有する.
- クラスターベースの分子固体は,特定の機能を持つ材料を設計するためのプラットフォームを提供します.
- 混合金属のイオン比を 制御することは 性質を調整する鍵です
研究 の 目的:
- 異なる鉄・コバルト比率の同構造の{Fe{9-x}Co{x}[W{CN}8]6{MeOH}24}·12MeOHクラスタを合成する.
- コントロールされた Co/Fe ステキオメトリがこれらのクラスタの磁気機能に与える影響を調査する.
- 電荷移転,相移転,磁気放緩現象の関係を解明する.
主な方法:
- ステイキオメトリックの組み合わせは,メタノール中のCo2+ ,Fe2+ ,および[WV]CN8− .
- 六角体中心の立方体トポロジーを持つペンタデカヌクレア群の構造的特徴.
- 電荷の移転,スピンクロスオーバー,磁気放緩を分析するスペクトル学および磁気学の研究.
主要な成果:
- 一連の同構造の{Fe(9-x) Co(x) [W(CN) 8 6 ((MeOH) 24}·12MeOHクラスター (x=0-9) が成功して合成されました.
- 鉄に富んだフェーズ (0-5) は,電荷移転 (CT) とスピンクロスオーバー (SCO) に関連した熱誘導の可逆構造フェーズ移行 (180-220 K) を表している.
- コバルトが豊富なフェーズ (6-9) は,コバルト含有量が増加するにつれて,磁気リラックスのためのエネルギーバリアが増加します.
結論:
- これらのクラスターの Co/Fe 比率は,前例のない磁気機能のチューニングを可能にします.
- Fe-NC-W結合は相変化を促進し,Co-W CTISTは構造変化と磁気ヒステリシスを強化する.
- これらのクラスターベースの分子固体溶液は,高度なアプリケーションのための調整可能な磁気行動を持つユニークな材料のクラスを表します.
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