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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
ビピリジンとディアザブタジエンのデカメチルテルボセンの複合体:多構成基底状態とオープンシェルのシングレット形成
Corwin H Booth1, Marc D Walter, Daniel Kazhdan
1Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. chbooth@lbl.gov
Journal of the American Chemical Society
|April 24, 2009
まとめ
デカメチルイテルボセンの複合体は,f-軌道占有により,中間のバレンスを示し,開いた殻のシングレット形成を示す. この発見は,オルガノランタニド化合物とf元素化学における異常な磁性を明らかにする.
科学分野:
- 有機金属化学 有機金属化学
- マテリアルサイエンス 材料科学
- 量子化学とは,量子化学である.
背景:
- デカメチルテルボセンは, (C ((5) Me ((5)) ((2) Yb (Cp * ((2) Yb),ビピリジンとディアザブタジエンのリガンドとアダクトを形成する.
- これらのアダクトに異常な磁気特性が見られ,その電子構造の調査を促した.
研究 の 目的:
- 電子構成,特に部分イテルビウムf軌道占有率とオープンシェルシングレット形成をCp*(2) Ybアダクトで確立する.
- これらのオルガノランタニド複合体における観測された磁気行動の起源を解明する.
主な方法:
- Yb L(III) 縁のX線吸収近縁構造 (XANES) のスペクトロスコピーを用いて,バレンスを決定する.
- 磁気特性を探査するための磁気感受性測定.
- 完全なアクティブスペース自己一貫性フィールド (CASSCF) の多構成計算.
- 密度関数理論 (DFT) による計算による構造分析.
主要な成果:
- 中間バレンスを示す部分的なイテルビウムf軌道占有が確認されました.
- 複数の構成のグラウンドステート波関数で特徴づけられる,オープンシェルのシングレット形成が,f(13) ((pi*) ((1) とf(14) のコンポーネントで特定されました.
- 中間バレンスの温度依存性の欠如は,磁気に対する代替理論を排除した.
結論:
- この研究は,Cp*(2) Yb誘導体における中間値能とオープンシェルシングレット形成を確立している.
- これらの発見は,オルガノランタニドおよびf元素化学における化学結合の洞察を提供します.
- この結果は,ナノ粒子や機器などの高度な材料における磁気相互作用を理解するための意味を持つ.
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