在二复合体中,X射线光谱对电子结构和金属-金属结合的描述
Arun S Asundi1, Roel L M Bienenmann2, Daniël L J Broere2
1Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States.
研究人员探索了双复合体,揭示了连接物协调和对称性如何决定金属对金属的结合. 通过X射线光谱和计算,在伪八面体,但不是伪四面体的几何结构中确定了Co-Co键.
科学领域:
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
- 量子化学 是一个量子化学.
背景情况:
- 开发具有可调节金属对金属相互作用的多金属复合物是合成无机化学的一个关键目标.
- 由于系统依赖的因素,了解金属对金属的结合及其对化学性质的影响是复杂的.
研究的目的:
- 为了阐明双复合体中的电子结构和粘合.
- 为了研究连接体协调和对称性在决定金属对金属键形成中的作用.
主要方法:
- 使用X射线吸收和辐射光谱分析电子结构.
- 量子化学计算被用来补充实验数据.
- 研究了一系列具有不同协调几何形状的双复合体.
主要成果:
- 双复合物与西兰联体和伪八面体几何学表现出Co-Co sigma和多中心结合.
- 由于对称性约束,具有伪四面体协调几何学的二复合体没有显示Co-Co结合.
- 光谱和计算分析提供了对被占用和空置电子状态的见解.
结论:
- 连接体协调和对称性是决定Co-Co键存在或不存在的关键因素.
- 射线光谱学和量子化学计算为金属对金属相互作用提供了基本的见解.
- 这项研究指导了具有可调节的金属-金属键的多金属复合体的合理设计.
更多相关视频
06:53Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
10:03Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
相关概念视频
Colors and Magnetism
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...
Valence Bond Theory
Crystal Field Theory - Octahedral Complexes
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...
Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2âÃÂÃÂy2 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 dx2âÃÂÃÂy2 and dz2 orbitals (along the Cartesian axes)...
Bonding in Metals
Metal-Ligand Bonds
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...
