溶剤依存の可逆の"オン"と"オフ"交換バイアスの振る舞いを示すサイアニド単分子磁石
Dawid Pinkowicz1, Heather I Southerland2, Carolina Avendaño2
1Faculty of Chemistry, Jagiellonian University , Ingardena 3, 30-060 Kraków, Poland.
Journal of the American Chemical Society
|November 7, 2015
まとめ
マンガンと重過渡金属を含む新しい複合塩は,切り替え可能な単分子磁石と交換バイアスの性質を示す. 溶解は磁気特性を著しく高め,磁気緩解を改善するために重い元素の重要性を示している.
科学分野:
- 協調化学
- 材料科学
- マグネティズム
背景:
- 単分子磁石 (SMM) は,高度な磁石材料の開発に不可欠です.
- SMMの特性における金属イオンと溶媒の役割を理解することは不可欠です.
- アニゾトロピック交換相互作用は,複合塩の磁気行動に影響する.
研究 の 目的:
- SMMと交換バイアスの可能性のある新しい複合塩を合成し,特徴づける.
- 磁気特性に対するインタースティシャルメタノール含有量の影響を調査する.
- SMMの性能に対する重過渡金属 (Os, Ru) の影響を調査する.
主な方法:
- 新しい複合塩の合成: (PPN) {[Mn (III) (サルフェン) (MeOH) ]2[M (III) (CN) ]6}·7MeOH (M = Fe, Ru, Os, Co) と混合Co/Osアナログ.
- SMMの行動と交換バイアスの効果を含む磁性特性測定.
- 不弾性ニュートロン散乱とTHz電子パラマグネティック共振スペクトロスコーピー.
主要な成果:
- すべての合成化合物は,メタノール含有量に依存するスイッチ可能なSMMと交換バイアスの振る舞いを示す.
- Mn2Os·7MeOHの溶解により,エネルギーバリア (Ueff/kB) が17.1Kから42.0Kに大きく増加し,ヒステレスループが開きます.
- 重過渡金属 (Os,Ru) の導入は,Mn (III) とOs (III) イオン間のアニゾトロプ的交換相互作用を特定して,SMMの性質を高めます.
結論:
- メタノール含有量は,これらの複雑な塩の磁性特性に重大な影響を及ぼします.
- 重過渡金属は,SMMの磁気化の緩やかな緩解を改善するために不可欠です.
- 観測された磁気現象において,アニゾトロピック交換相互作用が重要な役割を果たしている.
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