低座標のサイクルアルキル (((アミノ)) カーベンの安定化鉄 (((I) 複合体の電子構造と緩やかな磁気緩和
Prinson P Samuel1, Kartik Chandra Mondal, Nurul Amin Sk
1Institut für Anorganische Chemie, Georg-August-Universität , Tammannstrasse 4, D-37077, Göttingen, Germany.
Journal of the American Chemical Society
|July 30, 2014
まとめ
サイクルアルキルアミノカルベンによって安定化された新しい鉄 (I) 複合体は,単一分子磁石の性質を示します. これらの発見は,低価鉄の化学と磁性材料の理解を前進させる.
科学分野:
- 無機化学 無機化学とは
- 材料科学 材料科学とは
- 量子化学とは,量子化学である.
背景:
- 低価鉄複合体は,独自の電子構造と潜在的な応用により,大きな関心を持っています.
- 周期性アルキル・アミノ) カーベン (cAACs) は,金属の異常な酸化状態を安定させることができる多機能リガンドである.
研究 の 目的:
- cAACリガンドによって安定化された新しい2座標と3座標のFe (((I)) 複合体を合成し,特徴づけること.
- これらのFe (I) 化合物の磁気特性および電子構造を調査する.
- 単一分子磁石としての潜在能力を探求するためです.
主な方法:
- (cAAC) 2FeClと[cAAC) 2Fe][B][C6F5) ]4複合体の合成について
- 磁気感受性の測定. 磁気感受性の測定. 磁気感受性の測定. 磁気感受性の測定.
- モッズバウアー光譜法. モッズバウアー光譜法.
- 高周波電子パラマグネティック共振 (EPR) スペクトロスコーピー.
- MOLCAS.を使用した初期計算 (CASSCF/CASPT2/RASSI-SO)
主要な成果:
- 特徴付けにより,Fe ((I)) 酸化状態とS = 3/2スピンの基底状態が両複合体で確認されました.
- 両化合物は,適用されたDC磁場の下での単一分子磁石の特性である遅い磁気緩和を示した.
- EPR測定は,化合物2の大きい正のゼロフィールド分裂 (∼20.4cm(-1)) と簡単な平面アニソトロピーを明らかにしました.
- 理論的な計算は,電子構造と磁気特性に関する実験的発見を裏付けました.
結論:
- この研究では,CAACリガンドによって安定した新しいFe ((I)) 複合体を準備し,特徴づけることに成功しました.
- これらの複合体は,単一分子磁石の振る舞いを示しており,その理由は,S = 3/2 の基本状態と,重要なゼロフィールド分割によるものである.
- この発見は,分子磁性材料の開発に貢献し,低価鉄化学の理解を深める.
関連する概念動画
03:02Colors and Magnetism
12.0K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
12.0K
02:42Valence Bond Theory
8.9K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
8.9K
01:09Complexation Equilibria: Factors Influencing Stability of Complexes
989
In complexation reactions, metal cations are the electron pair acceptors, and the ligands are the electron pair donors. The stability of the metal complexes depends primarily on the complexing ability of the central metal ion and the nature of the ligands. Generally, the complexing ability of the metal ion depends on the size and charge of the ion. As the metal ion size increases, the stability of the metal complexes decreases, provided that the valency of the metal ion and the ligands remain...
989
02:58Crystal Field Theory - Octahedral Complexes
28.4K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
28.4K
02:34Structural Isomerism
16.8K
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly,...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly,...
16.8K
01:27π Electron Effects on Chemical Shift: Overview
1.5K
An applied magnetic field causes loosely bound π-electrons in organic molecules to circulate, producing a local or induced diamagnetic field over a large spatial volume. As the molecules tumble in solution, the field generated by π-electrons in spherical substituents results in a zero net field. However, the net field generated by π-electrons in non-spherical substituents is not zero. The effect of this induced field depends on the orientation of the molecule with respect to B0,...
1.5K