ポリマーチェーン分子磁石のクラスター間交換経路 Cu (((hfac) 2L (((R) は,電子パラマグネティック共振によって明らかにされています
Matvey V Fedin1, Sergey L Veber, Ksenia Yu Maryunina
1International Tomography Center SB RAS, Institutskaya str. 3a, 630090 Novosibirsk, Russia. mfedin@tomo.nsc.ru
Journal of the American Chemical Society
|September 16, 2010
まとめ
分子磁石 Cu ((hfac) ((2) L (((R) は磁気スイッチングを示しています. 電子パラマグネティック共振 (EPR) により,磁気鎖は1Dであり,スピントライアードで構成されており,ポリマー鎖自体ではありません.
科学分野:
- マテリアルサイエンス 材料科学
- マグネチズム (磁気) とは
- 協調化化学について
背景:
- ポリマー鎖複合体 Cu ((hfac) ((2) L ((R)) は,磁気スイッチング現象を呈する.
- これらの分子磁石は,構造的ポリマー鎖に沿った1D磁石鎖を持つと考えられていた.
- 磁気異常における次元性の役割は完全に理解されていませんでした.
研究 の 目的:
- Cu ((hfac)) ((2) L ((R)) コンプレックスにおける磁気相互作用の真の次元性を解明する.
- 磁気鎖の性質とその構成要素であるスピン単位を決定する.
- 磁気単位間の交換カップリングを定量化するために.
主な方法:
- Q帯電子パラマグネティック共振 (EPR) スペクトロスコピーを用いた.
- 1回転と3回転ユニットの選択的探査は,EPR.を使用して達成されました.
- 結果は磁気感受性データと量子化学計算と相関した.
主要な成果:
- 交換チャネルでは磁気鎖は1Dであるが,構造的ポリマー鎖に広がっていることが示された.
- 磁気鎖は,スピントライアード (ニトロキシド-銅 (II) -ニトロキシド) のみで構成されていることが判明した.
- スピントライアード間の量化された連鎖間交換カップリング値,<1~~10cm~-1).
結論:
- Cu ((hfac) ((2) L ((R)) 複合体の磁気構造は,ポリマーの骨格ではなく,1Dのスピントライアードに基づいています.
- 協調性の効果と磁気スイッチングメカニズムの精密な理解を提供します.
- 分子磁石の設計原理に関する新しい洞察を提示します.
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