テトラシアノピラジニドジメールダイアニオン, [TCNP]2(2-). 2電子の8センター結合による2電子結合です
Juan J Novoa1, Peter W Stephens, Mahika Weerasekare
1Departament de Química Física and IQTCUB, Facultat de Química, Universitat de Barcelona, Av. Diagonal 647, 08028-Barcelona, Spain. juan.novoa@ub.edu
Journal of the American Chemical Society
|June 6, 2009
まとめ
クロミウム(0) ベンゼン複合体とテトラシアノピラジン (TCNP) の間の反応は,TCNPの根幹アニオンジマーを形成する. このダイマーです.
科学分野:
- 協調化化学について
- 超分子化学 超分子化学
- マテリアルサイエンス 材料科学
背景:
- 新規の調整複合体の合成と特徴づけは,新しい材料の開発において極めて重要です.
- ラジカルアニオン二重体における電子構造と結合の理解は,電子離位化と分子間相互作用の洞察を提供します.
研究 の 目的:
- ビス・ベンゼン・クロム・クロム0と1,2,4,5-テトラシアノピラジン (TCNP) の間の反応を調査する.
- 結果的に発生した複合体と形成されたTCNPの根幹アニオンジマーを特徴付けるため.
- 計算的方法を用いてTCNPダイマーの結合と安定性を解明する.
主な方法:
- [Cr ((C ((6) H ((6))) ((2))) [TCNP]複合体の合成.
- 覆われたpi-[TCNP](2)(2-) 二次元の結晶学的分析.
- 分子内の原子 (AIM) 分析.
- 密度関数理論 (DFT) 計算 (B3LYP/6-31+G(d)) で分子間相互作用を研究する.
主要な成果:
- この反応は[Cr(C(6) H(6)) (((2) ]][TCNP]を生成し,TCNPはPi-[TCNP](2) (((2-) ダイマーに還元される.
- ダイア磁性TCNPダイマーは,3.14(2) Åのイントラダイマー分離を示し,C-CとN-Nの分離はそれぞれ3.29(2) と3.42(2) Åである.
- AIM分析は,2電子/8中心のC−C結合が二次体内にあることを示唆している.
- 計算による研究では,反発性のある二次体内TCNP-TCNP相互作用 (−58.9 kcal/mol) が示され,安定性は主にTCNP基離子と反作用 (−209.8 kcal/mol) の間の静電相互作用によって導かれる.
結論:
- TCNPの根性アニオンジメルの安定性は,直接のTCNP-TCNP結合ではなく,主にコントラケーションとの静電相互作用によって支配されます.
- 観察された構造的歪みは,ニトリル曲折を含む,これらの安定電静力によって影響を受けます.
- この研究は,TCNPのラジカルアニオン二重体内の電子構造と分子間力の詳細な理解を提供します.
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