ビスタブルな多機能性と切替可能な強い鉄磁気対抗鉄磁気結合は,一次元的なロジウム (I) -セミキノナト複合体で作られています
Minoru Mitsumi1, Takashi Nishitani, Shota Yamasaki
1Department of Material Science and ‡Research Center for New Functional Materials, Graduate School of Material Science, University of Hyogo , 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan.
Journal of the American Chemical Society
|April 23, 2014
まとめ
この研究は,バイスタブルな磁気および伝導性特性を示す新しいロジウム (I) -セミキノナト複合体を明らかにしています. 独特の相変化により,圧力などの外部刺激によって制御された多機能性を可能にします.
科学分野:
- 無機化学 無機化学とは
- 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:
- 一次元の (1D) 協調複合体は,ユニークな電子および磁気特性を提供します.
- セミキノナトリンガンドは,磁気相互作用を媒介し,結晶包装に影響を与えることができます.
- 温度や圧力などの外部刺激によって材料の性質を調節することは,材料科学の重要な目標です.
研究 の 目的:
- 1Dロジウム ((I) -セミキノナト複合体の新型合成と特徴づけ.
- 複合体の磁気および電気的性質を調査し,潜在的な多機能性に焦点を当てます.
- 観察されたビスタビリティの背後にあるメカニズムとその外部の条件への依存を理解する.
主な方法:
- ロジウム ((I) -セミキノナト複合体の合成 [Rh ((3,6-DBSQ-4,5- ((MeO) 2) ((CO) 2) ∞.
- X線微分法を用いた構造分析.
- 磁気特性の特徴 (感受性,順序付け) について
- 電気伝導性と抵抗性の測定.
- 密度関数理論 (DFT) による計算.
主要な成果:
- この複合体は,熱ヒステリゼによる第1次相移行により,特定の温度範囲 (228-207 K) 内で,前例のない2度性磁気および伝導性特性を示しています.
- 低温相における強い鉄磁気相互作用は,室温相における反鉄磁気相互作用への低温相への移行である.
- 遠距離アンチフェロマグネティック・オーダーリングと14.2Kで自発的な磁化.
- 比較的高い電気伝導度 (4.8 × 10−4 S cm−1) が300 Kで,抵抗性もヒステレスを示している.
- 鉄磁気低温相は,適度な圧力 (1.4 kbar) を使用して室温で安定させることができます.
結論:
- ロジウム (I) -セミキノナト複合体は,水素結合の変化を含む構造的相変遷によって誘発される,顕著な二元化可能な多機能性を示しています.
- 分子堆積,磁気相互作用 (鉄磁気から反鉄磁気) と電気伝導性の相互作用は顕著である.
- 外部刺激,特に圧力は,素材の多機能状態を効果的に制御し,安定させることができ,切り替え可能な電子機器への道を開きます.
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