Mn[N(CN) 2) 2 ((pyz) (pyz = ピラジン) での長距離磁気順序である. 感受性,磁気化,比熱,中性子 difraktion 測定,電子構造の計算などを行いました
J L Manson1, Q Huang, J W Lynn
1Department of Chemistry, University of Utah, Salt Lake City, Utah 84112-0850, USA. jlmanson@anl.gov
Journal of the American Chemical Society
|March 29, 2001
まとめ
この研究では,Mn[N(CN) 2) 2 ((pyz) は主に1次元の磁気系を示し,反鉄磁気配列は2.53K以下である.単離離体アニソトロピーにより,フィールド誘発の移行が観察された.
科学分野:
- 材料科学 材料科学とは
- 固体物理 固体物理学
- マグネティズム (磁気) とは
背景:
- マンガン基のコーディネーションポリマーは,調節可能な磁気特性を提供します.
- 低次元システムにおける磁気配列の理解は,材料設計において極めて重要です.
研究 の 目的:
- Mn[N(CN) ]2[pyz]の磁気特性と磁気構造を徹底的に調査する.
- この材料における磁気相互作用の性質と次元性を解明する.
主な方法:
- DC磁化,AC感受性,特異熱測定について.
- 結晶学および磁気構造の決定のためのニュートロン粉の difraktion.
- リートヴェルドの精錬と電子構造の計算.
主要な成果:
- T(N) = 2.53(2) K以下で観測された反鉄磁気順序は,それに相応しい磁気構造を持つ.
- 強いMn-pyz-Mn連鎖相互作用によって説明される1次元の磁気行動が優勢である.
- ハイゼンベルクの反鉄磁気連鎖モデルは,磁気感受性のデータを成功裏に記述しています.
- 0.43Tと2.83Tで観測されたフィールド誘発のスピンフロップとパラマグネティック移行.
結論:
- Mn[N(CN) 2) 2 ((pyz) は,準一次元反鉄磁石である.
- シングルイオンアニソトロピーは,磁場誘発の磁気現象において重要な役割を果たします.
- この研究は,マンガンの協調ポリマーの磁気行動に関する詳細な洞察を提供します.
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