通过桥接氧胺酸二离子的链接异构体,修改二摩单元中的电子通信
F Albert Cotton1, Chun Y Liu, Carlos A Murillo
1Laboratory for Molecular Structure and Bonding, Department of Chemistry, P.O. Box 30012, Texas A&M University, College Station, Texas 77842-3012, USA. cotton@tamu.edu
Journal of the American Chemical Society
|October 30, 2003
概括
研究人员合成了由氧胺酸离子桥接的异构二核化合物. 贝塔异构体表现出优越的电子通信,由间隔电荷传输带证明,与α异构体不同.
科学领域:
- 无机化学 无机化学 有机化学
- 有机金属化学 有机金属化学
- 材料科学 材料科学 材料科学
背景情况:
- 双核化合物具有独特的电子和结构性质.
- 氧化二离子在协调化学中充当了多功能桥梁连接体.
研究的目的:
- 为了合成和表征由氧胺酸连接体桥接的同质二核复合体.
- 为了研究电子通信和α和β异构体之间的结构差异.
主要方法:
- [Mo(2) ]复合物的合成与氧胺酸二.
- 用光谱分析 (UV-Vis,电化学) 来探测电子通信.
- 分子力学和密度函数理论 (DFT) 计算用于结构和能量分析.
主要成果:
- 获得了两对同位体化合物 (α和β),它们在胺酸桥和Mo-Mo键的相对方向上有所不同.
- 贝塔异构体表现出明显更好的电子通信,以较低的氧化电位差异 (DeltaE(1/2) 表示.
- 对氧化β异构体观察到近红外间距电荷转移带,但对α异构体没有观察到.
结论:
- 阿尔法和β异构体之间的构造差异决定了它们的电子通信特性.
- 氧化桥式双核复合物提供基于异构结构的可调节电子特性.
- DFT计算提供了观察到的形状偏好和能量差异的见解.
更多相关视频
相关概念视频
Ionic Bonding and Electron Transfer
Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Compounds composed of ions are called ionic compounds (or salts), and their constituent ions are held together by ionic bonds: electrostatic forces of attraction between oppositely charged cations and anions.
Electron Transport Chain: Complex I and II
The mitochondrial electron transport chain (ETC) is the main energy generation system in the eukaryotic cells. However, mitochondria also produce cytotoxic reactive oxygen species (ROS) due to the large electron flow during oxidative phosphorylation. While Complex I is one of the primary sources of superoxide radicals, ROS production by Complex II is uncommon and may only be observed in cancer cells with mutated complexes.
ROS generation is regulated and maintained at moderate levels necessary...
ROS generation is regulated and maintained at moderate levels necessary...
Electron Transport Chain: Complex III and IV
During the electron transport chain, electrons from NADH and FADH2 are first transferred to complexes I and II, respectively. These two complexes then transfer the electrons to ubiquinol, which carries them further to complex III. Complex III passes the electrons across the intermembrane space to Cyt c, which carries them further to complex IV. Complex IV donates electrons to oxygen and reduces it to water. As electrons pass through complexes I, III, and IV, the energy released aids the pumping...
Ion Exchange
Ion exchange chromatography separates charged molecules from a solution by reversibly exchanging them with mobile, or 'active', ions associated with the oppositely charged stationary phase. This method can be used to separate ions, soften and deionize water, and purify solutions. The polymers comprising the ion-exchange column are high-molecular-weight and chemically stable polymers, crosslinked to be porous and essentially insoluble. They are also functionalized with either acidic or basic...
Ionic Association
The ionic association is the association of oppositely charged ions in an electrolyte solution to form ion pairs. Bjerrum defined ion pairs as two oppositely charged ions whose electrostatic attraction exceeds the thermal energy of the system, typically expressed as 2kT. Electrostatic attraction depends on ionic charge, separation distance, and the dielectric constant of the medium. Thermal energy, represented by kT, reflects the tendency of ions to move independently due to molecular motion.
The Electrical Double Layer
In the region where two bulk phases meet, an intricate electric charge distribution arises due to charge transfer, ion adsorption, molecular orientation, and charge distortion. This complex distribution is commonly referred to as the electrical double layer.When a solid electrode interfaces with ions in an electrolyte solution, the speed of electron transfer dictates the rates of oxidation and reduction. The electrode acquires a charge through the escape of atoms into the solution as cations or...


