Spin-Crossover Polyanionic Fe ((II) トリマーにおける容易な興奮状態のトラッピングと記録的な高性能
Verónica Gómez1, Cristina Sáenz de Pipaón1, Pilar Maldonado-Illescas1
1Institute of Chemical Research of Catalonia (ICIQ), Avinguda Paisos Catalans 16, E-43007 Tarragona, Spain.
Journal of the American Chemical Society
|September 5, 2015
まとめ
多硫化トリアゾールリガンドを持つ新しい鉄複合体は,室温以上でスピン移行を示しています. これはスイッチ可能な分子材料にとって不可欠な高スピン状態の熱捕捉を可能にします.
科学分野:
- 協調化学
- 材料科学
- マグネト化学
背景:
- スピン・クロスオーバー (SCO) 材料は,分子スイッチとメモリデバイスに興味があります.
- 高度な移行温度と遅いダイナミクスを有するSCO材料の開発は重要な課題です.
研究 の 目的:
- 熱的に誘発されたスピン移行を示す新しい鉄 (II) 複合体を合成し,特徴づけること.
- 合成材料のスピンダイナミクスと熱捕捉特性を調査する.
主な方法:
- ポリ硫化トリアゾールリガンドによるトリメル鉄 (III) 複合体の合成.
- 複合体の磁気特性の特徴,スピン移行とヒステリシスを含む.
- 高スピン状態のリラックスダイナミクスの分析.
主要な成果:
- [Fe3 ((μ-L) 6 ((H2O) 6)) コンプレックスは合成され,二メチルアモニウム塩として分離された.
- 温室温度の上の中心のFe (II) イオンについて,熱的に誘導されたスピン移行が観察された.
- 大きなヒステリシスサイクル (>85 K) と遅いスピンダイナミクスが検出され,高スピン状態の容易な消火と捕獲が可能になりました.
- 高スピン状態は215K以下で,熱誘発刺激スピン状態のトラップと安定化 (TTIESST) の特徴的な温度250Kにとどまった.
結論:
- 合成された鉄 (II) 複合体は,交換可能な分子材料のための有望な性質を示しています.
- 観測された高い移行温度と遅いダイナミクスは,SCO材料の重要な進歩を表しています.
- この材料は 独特の熱捕捉能力により 分子電子や センシングの応用の可能性があります
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