非結合型,混合型,ホモメタリックイテルビウム複合体における間隔電荷移転
Michael D Roy1, Thaige P Gompa1, Samuel M Greer2
1School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States.
Journal of the American Chemical Society
|February 19, 2024
まとめ
研究者は,短距離のYb-Ybを持つ混合バレンスのイテルビウム複合体を合成し,分子ランタニド系における最初の間隔電荷移転 (IVCT) を実証した. この発見は,混合酸化状態のランタニド化合物の電子構造を調整するための新しい道を開きます.
科学分野:
- 無機化学
- 材料科学
- 量子化学について
背景:
- 複数の酸化状態を持つランタニド複合体は珍しい.
- インターバレンスの電荷移転 (IVCT) は分子ランタニド系ではめったに観察されず,通常は拡張固体に限定される.
- 短いランタニド-ランタニド (Ln-Ln) 距離が報告されており,しばしば5d軌道相互作用に起因する.
研究 の 目的:
- 新しいイテルビウム複合体を合成し,特徴づけること.
- 混合バレンスのランタニド系における電子構造と結合を調査する.
- 分子ランタニド複合体における間隔電荷伝送 (IVCT) を観察し分析する.
主な方法:
- イテルビウム複合体の合成
- 顕微鏡と結晶学的技術を用いた特徴付け
- 電子構造と結合の計算分析
主要な成果:
- 混合バレンスのYb2^5+複合体は,短いYb-Yb距離 (2.9507(8) で合成された.
- 複合体はYb2+とYb3+の明確な局所化を示している.
- 分子ランタニド系では初めて,可視スペクトルで間隔電荷移転 (IVCT) が観察された.
結論:
- この研究は,混合酸化状態のランタニド複合体の電子構造を調節する能力を示しています.
- Yb2+ (4f14) コンフィギュレーションの高い交換安定化は5d1結合を不利にします.
- リガンドフレームワークによって強制された短い金属-金属距離は,分子システムにおけるランタニドIVCTの観測を可能にします.
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