"移行金属を模倣するアルカリ土複合体M (CO) 8 (M = Ca,Sr,またはBa) の観測"に関するコメント
Clark R Landis1, Russell P Hughes2, Frank Weinhold3
1Department of Chemistry, University of Wisconsin, Madison, WI 53706, USA. landis@chem.wisc.edu.
Science (New York, N.Y.)
|August 10, 2019
まとめ
カルシウム,ストロンチウム,バリウムなどのアルカリ土金属のオクターカーボニルは,移行金属結合を模倣しない. この研究は,欠陥のあるエネルギー分解分析方法に基づいた主張を否定しています.
科学分野:
- 無機化学
- 量子化学について
- 材料科学
背景:
- 最近の研究では,アルカリ土金属 (Ca,Sr,Ba) のオクターカーボニル化合物は,移行金属と同様の結合を示唆している.
- この提案されたデワー・チャット・ダンカンソン結合モチーフは,これらの主要なグループ金属化合物における確立された化学的原理に挑戦しています.
研究 の 目的:
- Ca,Sr,Baのオクターカーボニルがデワー-チャット-ダンカンソン結合モチーフを模倣するという主張を批判的に評価する.
- クレームと既知の化学的理解の間の不一致の源を特定する.
主な方法:
- 報告されたエネルギー分解分析 (EDA) の分析
- 計算された電子密度分布の検討.
- 化学結合の確立された原理との比較.
主要な成果:
- デワー-チャット-ダンカンソン結合モチーフの主張された模倣は根拠のないものであることが示されている.
- 元の研究で使用されたエネルギー分解分析は,欠陥のある基準状態に基づいています.
- 計算された電子密度分布は,提案された結合モデルをサポートしません.
結論:
- Ca,Sr,Baのオクターカーボニルは古典的なデワール-チャット-ダンカンソン結合モチーフを示さない.
- 誤った結論は,参考研究における根本的に欠陥のある理論的アプローチから生じている.
- 主なグループ金属カルボニルの結合の再評価は,健全な理論的方法に基づいて必要である.
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