2つの結合されたジモリブデンウム単位を含む分子の完全に局所化された混合バレンスの酸化産物:効果的な構造的基準
F Albert Cotton1, Naresh S Dalal, Chun Y Liu
1Laboratory for Molecular Structure and Bonding, Department of Chemistry, P.O. Box 30012, Texas A&M University, College Station, Texas 77842-3012, USA. cotton@tamu.edu
Journal of the American Chemical Society
|October 16, 2003
まとめ
化学的に酸化するジモリブデン化合物は,1電子の酸化により,ペア化されていない電子を単一のMo (((2) (((4+) 単位で局所化することを明らかにします. 2電子の酸化により,同等のMo(2) 単位が得られ,両種ともバレンスのトラップが認められる.
科学分野:
- 無機化学 無機化学とは
- 協調化化学について
- マテリアルサイエンス 材料科学
背景:
- 以前に報告された化合物は,四重結合したMo (((2) (((4+)) 単位を特徴としています.
- これらの単位は,特定のアニオンリガンドによって安定させられます.
研究 の 目的:
- 化学的酸化がダイモリブデン化合物に及ぼす影響を調査する.
- 酸化時の電子的および構造的変化を特徴付けるために.
主な方法:
- 先駆体化合物の化学的酸化.
- 酸化製品のX線結晶学を用いた分離と構造的特徴付け.
- 電子パラマグネティック共振 (EPR) スペクトロスコーピー.
- 磁気感受性の測定 磁気感受性の測定 磁気感受性の測定
主要な成果:
- 一電子酸化は,非対称な構造と異なるMo-Mo結合長を持つ混合バレンスのカチオンを生み出し,電子の局所性を示します.
- EPRスペクトルは,ペア化されていない電子の1つのMo(2) 単位での局所化をサポートします.
- 2電子の酸化により,特徴的なMo-Mo結合距離を持つ等価なMo(2) 単位が得られます.
- 二重酸化された種のEPRと磁気感受性データは,有意なスピンカップリングを示さないため,バレンスのトラップを暗示しています.
結論:
- これらのジモリブデン化合物の酸化はMo(2) 単位で起こります.
- 混合バレンスの種は,固体状態で電子的に局所化されます.
- この二重酸化化合物は,バレンチ・トラップされ,Mo(2) ユニット間の有意な磁気結合はありません.
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