对连接体动力学的结构洞察:在氧科巴尔特中相关的氧气和杆运动杆杆杆杆杆杆杆酸
Jianfeng Li1, Bruce C Noll, Allen G Oliver
1College of Materials Science and Opto-electronic Technology, Graduate University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China.
Journal of the American Chemical Society
|May 31, 2012
概括
对类二烯的结构分析揭示了温度依赖的氧联体动态和乱. 了解这些氧相互作用是模拟生物系统中类似过程的关键.
科学领域:
- 无机化学 无机化学 有机化学
- 晶体学 晶体学是指结晶学.
- 生物模拟化学 生物模拟化学
背景情况:
- 类酸盐是生物系统中氧气运输的关键模型.
- 了解氧气与金属中心结合的动态对于生物无机化学至关重要.
研究的目的:
- 为了合成和结构性地描述与氧结合的类.
- 为了研究氧联体和保护组的温度依赖的动态和乱.
- 为了将结构发现与与蛋白质环境相关的M-O(2) 动态联系起来.
主要方法:
- 合成两种不同的与氧结合的类氨酸:[Co(TpivPP) ((1-EtIm) ((O(2)) ]和[Co(TpivPP) ((2-MeHIm) ((O(2)) ].
- 在多种温度 (100 K,200 K,300 K) 上使用X射线晶体学进行固态结构确定.
- 固态氧化反应和受控脱气实验.
主要成果:
- 在[Co(TpivPP) ((1-EtIm) ((O(2))) 中观察到氧联体和伊米达群的温度依赖性障碍.
- 确定了一种可逆的相位过渡,将派对小组障碍与围绕Co-O(O(2)) 债券的O(2) 旋转相关联.
- [Co(TpivPP) ((2-MeHIm) ((O(2)) ]在高O(2) 暴露 (5 atm) 时显示出完全的排队障碍,在脱气时恢复.
结论:
- 固态结构为氧键的动态行为提供了关键的见解.
- 保护群体障碍与氧气连接体旋转直接相关.
- 这些发现为建模金属蛋白中M-O(2) 动态提供了基本数据.
相关概念视频
02:51Metal-Ligand Bonds
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...
02:42Valence Bond Theory
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...
02:58Crystal Field Theory - Octahedral Complexes
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...
02:40MO Theory and Covalent Bonding
The molecular orbital theory describes the distribution of electrons in molecules in a manner similar to the distribution of electrons in atomic orbitals. The region of space in which a valence electron in a molecule is likely to be found is called a molecular orbital. Mathematically, the linear combination of atomic orbitals (LCAO) generates molecular orbitals. Combinations of in-phase atomic orbital wave functions result in regions with a high probability of electron density, while...
03:02Colors and Magnetism
Color in Coordination Complexes
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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 eye.
02:34Structural Isomerism
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 be...
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 be...