在f-元素复合体中探索共价性:二甲基酸联体揭示了重型动因化物和兰坦化物之间的差异
William Quintero-Martinez1,2, Dayán Páez-Hernández2,3
1Doctorado en Fisicoquímica Molecular, Universidad Andres Bello, República 275, Santiago 8370146, Chile.
Inorganic chemistry
|February 14, 2025
概括
乙化物和化物中的共价性显著不同. 沉重的活性化物表现出更大的共价性,特别是在更高的氧化状态下,由能量退化而不是轨道重叠驱动,硫连接物增强了这种效应.
科学领域:
- 无机化学 无机化学
- 量子化学 是一个量子化学.
- 理论化学 理论化学
背景情况:
- 协同性是理解活性化物和化物特性的关键.
- 电子结构的差异导致不同的化学行为.
- 狄氏碳酸联体为研究f元素结合提供了一个独特的系统.
研究的目的:
- 系统地分析行为化物和化物复合物的共价性.
- 为了比较actinides与lanthanides的结合特性.
- 为了阐明驱动f元素共价的因素.
主要方法:
- 分析三价和四价乙化物 (U-Fm) 和化物 (Nd-Er) 复合物的分析.
- 斯莱特-康登参数的应用.
- 使用分子中原子的量子理论 (QTAIM) 与键关键点 (BCP) 和自然局部分子轨道 (NLMOs).
- 包括多配置效应,标量相对论效应和旋转轨道合.
主要成果:
- 在重型活性化物和化物之间观察到对应性的显著差异.
- 较高的共价度与金属离子中较高的氧化状态相关.
- 据QTAIM分析,重型活性化物中的能量退化驱动的共价是重型活性化物,而不是轨道重叠.
- 硫供体原子比氧更能促进重型活性化物中的共价.
结论:
- 与兰化物相比,重型活性化物显示出明显的共价性质.
- 沉重的活性化物中的共价受电子退化和软的供体原子 (如硫) 的影响.
- 这些发现确定了actinides比它们的兰坦化对应物更软的易斯酸.
更多相关视频
10:10Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes
Published on: July 28, 2018
6.4K
07:24Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
5.6K
相关概念视频
02:42Valence Bond Theory
8.4K
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...
8.4K
02:58Crystal Field Theory - Octahedral Complexes
26.1K
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...
26.1K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
41.2K
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,...
41.2K
02:51Metal-Ligand Bonds
20.5K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
20.5K
00:43Complexometric Titration: Ligands
873
Different monodentate and polydentate ligands are used as complexing agents in complexometric titration reactions. The formation of complexes by mono- and bidentate ligands involves two or more intermediate steps, limiting their use as complexing agents. In comparison, polydentate ligands can form complexes with metal ions in a single-step process, facilitating sharper end points. This means polydentate ligands, such as amino carboxylic acid derivatives, are most commonly employed in...
873
01:23Complexation Equilibria: Overview
598
Complexation reactions take place when dative or coordinate covalent bonds form between metal ions and ligands. The compounds formed in these reactions are called coordination compounds. The number of bonds formed between the metal ion and the ligands is called its coordination number. Generally, most metal ions in an aqueous solution are solvated by water molecules and thus exist as aqua complexes.
The equilibrium constant of the complexation reaction is represented as the formation constant...
The equilibrium constant of the complexation reaction is represented as the formation constant...
598