擬四面体 (pseudotetrahedral) のイオンでのスピン状態調節:四座標 [BP3]CoII-X システムの構造的および磁気的現象を検証する
David M Jenkins1, Jonas C Peters
1Division of Chemistry and Chemical Engineering, Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, CA 91125. USA.
Journal of the American Chemical Society
|May 12, 2005
まとめ
この研究では,シドオテトラエドールコバルト ((II) コンプレックスとトリス (((フォスフィノ) ボラートリガンドを調査しています. 研究者らは,S = 1/2とS = 3/2の両方のスピン状態がアクセス可能であり,一部の複合体はスピンクロスオーバーの振る舞いを示すことを発見しました.
科学分野:
- 協調化化学について
- 有機金属化学 有機金属化学
- 無機化学 無機化学とは
背景:
- 擬四面体コバルト (Pseudotetrahedral cobalt) 複合体は,その多様な電子的および構造的性質のために興味を惹きます.
- トリス ((phosphino) ボラート ([BP ((3))) リガンドシステムは,金属センターにユニークなステリックおよび電子環境を提供します.
研究 の 目的:
- [PhBP ((3)) ]と[PhBP ((iPr) ((3)) ]リガンドで支えられている一連の擬似四面体コバルト ((2)) 複合体を合成し,特徴づけること.
- これらのコバルト複合体の電子構造,スピン状態,幾何学的歪みを調査する.
- リガンド構造,協調幾何学,磁気特性との関係を探求する.
主な方法:
- 新型コバルトの合成 (II) アリロキシド,シロキシド,アリルチオラート,シリルチオラート複合体.
- 標準的な (1) H NMR,光学,電気化学,および溶液磁気測定を用いた特徴付け.
- 低温電子パラマグネティック共振 (EPR) と変温超伝導量子干渉装置 (SQUID) の磁化研究.
- 低温単結晶X線微分分析 低温単結晶X線微分分析 低温単結晶X線微分分析 低温単結晶X線微分分析 低温単結晶X線微分分析
- 密度関数理論 (DFT) 電子構造の計算.
主要な成果:
- [PhBP ((3)) ]と[PhBP ((iPr) ((3)) ]リガンドを持つ一連の擬似四面体コバルト ((II) コンプレックスが合成され,特徴づけられました.
- 複合体は,傘型とオフアシス型の2つの主要な歪みを表しています.
- 傘型歪み複合体は,S = 1/2 と S = 3/2 の両方の基底状態にアクセスすることができ,リガンドの性質とデント性によって影響を受けます.
- オフアックス歪んだ複合体は,S = 1/2の基本状態を独占的に満たしている.
- 擬四面体シロキシドは,固体状態では徐々にスピンクロスオーバーを示します.
- DFT計算は,他のコバルト座標幾何学と電子構造の関係をサポートします.
結論:
- 座標幾何学とリガンド環境は,擬四面体コバルト (II) 複合体のスピン状態に大きな影響を与える.
- スピンクロスオーバーの行動は,特定の擬四面体シルオキシド複合体において観察された.
- [BP(3) ]リガンドフレームワークは,コバルト複合体の特性を調節するための汎用性のあるプラットフォームを提供します.
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