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Updated: Jul 8, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
pt-pt核スピン-スピン結合定数の明らかに不規則な振る舞いの理論的調査
Jochen Autschbach1, Ciprian D Igna, Tom Ziegler
1Department of Chemistry, University of Calgary, Calgary, Alberta, Canada T2N 1N4. jochen.autschbach@chemie.uni-erlangen.de
Journal of the American Chemical Society
|January 23, 2003
まとめ
二核プラチナ複合体の核スピン-スピン結合定数J ((Pt-Pt) は,単にPt-Pt結合距離ではなく,リガンド効果と相対論的要因により大きく変化する. 計算による研究は,プラチナ-プラチナ結合におけるこれらの大きな違いを説明します.
科学分野:
- 無機化学 無機化学とは
- コンピューティング・ケミストリー
- 量子化学とは,量子化学である.
背景:
- 単一結合プラチナ-プラチナ (Pt-Pt) 核スピン-スピン結合定数J (((Pt-Pt) は,二核プラチナ複合体において有意な変動を示している.
- これらの変動は,Pt-Pt結合距離と明確な相関関係なしに,大きさの順序である可能性があります.
研究 の 目的:
- 二核のPt(I) 複合体のスピン-スピン結合を計算的に調査するために,特に[Pt(2) (((CO) ((6))) ((2+) と[Pt(2) ((CO) ((2) Cl ((4))) ((2-).
- 実験的なJ ((Pt-Pt) 値で観測された大きな差異を説明するために.
主な方法:
- 計算研究のために最近開発された相対論密度関数法を使用した.
- Pt-Pt結合に対する協調リガンドの影響と相対論的効果を分析した.
主要な成果:
- J(Pt-Pt) 値の実験的傾向を成功裏に再現した.例えば,複合体2の5250 Hz,複合体1の551 Hz.
- 結合定数へのリガンド効果と相対論的貢献の間の敏感な相互作用を特定しました.
結論:
- J ((Pt-Pt) の大きな差異は,リガンド協調と金属-金属,および金属-リガンド結合に対する相対論的影響の効果の組み合わせによるものである.
- 質的分子軌道図は,プラチナ-プラチナ核スピン-スピン結合における観測された傾向に対する直感的な説明を提供します.
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