金属-クロム複合体における金属-金属結合順序の体系的な変化
Laura J Clouston1, Randall B Siedschlag, P Alex Rudd
1Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455-0431, United States.
Journal of the American Chemical Society
|August 2, 2013
まとめ
研究者らは,マンガン,コバルト,ニッケルで新しい金属結合複合体を合成し,Mn-Cr複合体の5倍結合を明らかにした. これらの発見は,異なる第一列移行金属間の複数の結合の理解を進める.
科学分野:
- 無機化学 無機化学とは
- 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
背景:
- 異なる移行金属間の安定した多重結合は,特に第一列の元素の間で稀である.
- 以前の研究で,鉄クロム複合体の発見が報告され,さらなる探査の準備が進められました.
研究 の 目的:
- クロミウムと他の第一列移行金属 (Mn,Co,Ni) の新しいヘテロメタリック複合体を合成し,特徴づけること.
- これらの新しい複合体における金属-金属結合の性質と電子特性を調査する.
主な方法:
- M-Cr複合体 (M = Mn,Co,Ni) の合成について.
- X線結晶学を用いた特徴化.
- 結合と電子構造を分析するための理論計算 (DFT).
- サイクルボルトメトリーによる電気化学分析.
主要な成果:
- 3つの新しいM-Cr複合体の分離と構造的決定.
- 五重結合を示す極短のMn-Cr結合 (1.82 Å) の観測.
- シリーズ全体 (Mn から Ni) でのM-Cr結合距離と結合順序の体系的な変動.
- M-Cr結合の極化が増加し,複数の酸化還元現象が観察されました.
結論:
- この研究は,複数の金属対金属結合を持つヘテロメタリック複合体のファミリーを成功裏に拡張しました.
- 結合長,順序,および偏極化の傾向は,金属のd軌道エネルギーと収縮の違いによって説明されます.
- 複合体は豊富なリドックス反応を示し,多様な用途の可能性を秘めています.
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