在五坐标Fe(III) 复合体中,具有不同的轴向和赤道连接体环境的自旋状态能量和磁性异构性
Shalini Joshi1, Sabyasachi Roy Chowdhury1, Sabyashachi Mishra1
1Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, India. mishra@chem.iitkgp.ac.in.
Physical chemistry chemical physics : PCCP
|June 27, 2023
概括
研究人员修改了铁的三角形-双形复合体,以调整磁性异性质. 特定的连接体组合,如轴向-P/-As和赤道-Br/-I,在中间旋转状态中增强磁性异性质.
科学领域:
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
- 量子磁力 量子磁力 量子磁力
背景情况:
- 五角协调的三角形双体 (TBP) 铁 (III) 复合体对于理解磁性特性至关重要.
- 这些复合物的磁性异构性对连接体环境和电子自旋状态 (中间自旋与高自旋) 很敏感.
研究的目的:
- 系统地研究如何改变TBP Fe(III) 复合体中的联体环境会影响它们的磁性异构性.
- 识别特定的连接体组合,稳定所需的电子状态 (IS和HS) 并最大限度地提高磁性异构性.
主要方法:
- 一系列Fe(III) TBP复合物的合成和表征,具有修饰的轴和赤道连接体.
- 在中旋 (IS) 和高旋 (HS) 状态下对复合体进行计算建模,以了解电子结构.
- 基于连接体场理论和电子状态稳定性的磁性异构的分析.
主要成果:
- 较轻的带 (例如,-N, -F) 有利于HS状态,而较重的带 (例如,-P, -As, -Cl, -Br, -I) 稳定了磁性异构的IS状态.
- 特定的轴向/赤道连接体组合 (例如,轴向-P/-As与赤道-Br/-I) 通过创建几乎退化的地面电子状态,产生很大的磁性异质.
- 与甲基组相比,轴性乙基一般会增强异构性;赤道性会损害单轴性异构性,增加量子道化.
结论:
- 干选择对Fe(III) TBP复合体中的自旋状态和磁性异构性进行了关键控制.
- 定制连接体环境允许合理设计具有特定磁性质的材料,这与分子磁性和量子技术有关.
更多相关视频
09:06Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
8.2K
08:55Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
8.6K
相关概念视频
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
8.8K
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...
8.8K
02:58Crystal Field Theory - Octahedral Complexes
26.9K
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...
26.9K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
43.1K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
43.1K
02:34Structural Isomerism
19.5K
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, SCN− can...
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, SCN− can...
19.5K