在氧友金属系统中,双电子和四电子供体碳基之间的相互作用:高度不和的二多碳基
Qian-shu Li1, Xiuhui Zhang, Yaoming Xie
1Institute of Chemical Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China. qsli@bit.edu.cn
Journal of the American Chemical Society
|February 24, 2007
概括
密度函数理论揭示了divanadocene carbonyls的新型结构. 一个单一的Cp2V2(CO) 结构表现出异常短的-键,表明可能存在多重键.
科学领域:
- 有机金属化学 有机金属化学
- 计算化学计算化学
- 无机化学 无机化学
背景情况:
- 迪瓦纳多碳基 (Cp2V2(CO) n) 是有机金属化合物,具有异常结合的潜力.
- 了解它们的结构和电子特性对于推进协调化学至关重要.
研究的目的:
- 为了研究二多烯碳基 (Cp2V2(CO) n,n = 5, 4, 3, 2, 1) 的结构和电子特性.
- 使用计算方法探索粘合特性,包括金属-金属距离和桥接碳基模式.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 使用B3LYP和BP86函数来优化结构和确定能量.
- 分析了计算的金属-金属键距离和振动频率 (nu(CO)).
主要成果:
- 全球Cp2V2(CO) 5的最小结构与实验X射线衍射数据一致.
- Cp2V2(CO) 4表现出三重基态,具有较高能量的单元状态,具有不同的桥接碳基态和V-V距离.
- 脱碳化导致桥梁碳基的流行率增加,并预测Cp2V2 (CO) 的极短V-V距离 (1.80 Å),频率非常低.
结论:
- DFT计算提供了关于二多二氧化碳的结构多样性的见解.
- 这项研究强调了Cp2V2 (CO) 复合体中多个V-V结合的可能性.
- 这些发现有助于理解低价值过渡金属碳基的结合.
相关概念视频
01:29Covalent Bonds
When two atoms share electrons to complete their valence shells they create a covalent bond. An atom’s electronegativity—the force with which shared electrons are pulled towards an atom—determines how the electrons are shared. Molecules formed with covalent bonds can be either polar or nonpolar. Atoms with similar electronegativities form nonpolar covalent bonds; the electrons are shared equally. Atoms with different electronegativities share electrons unequally, creating polar bonds.A Covalent...
02:46Covalent Bonding and Lewis Structures
Compared to ionic bonds, which results from the transfer of electrons between metallic and nonmetallic atoms, covalent bonds result from the mutual attraction of atoms for a “shared” pair of electrons.
02:54Lewis Structures of Molecular Compounds and Polyatomic Ions
To draw Lewis structures for complicated molecules and molecular ions, it is helpful to follow a step-by-step procedure as outlined:
02:40Chemical Bonds
Atoms participate in a chemical bond formation to acquire a completed valence-shell electron configuration similar to that of the noble gas nearest to it in atomic number. Ionic, covalent, and metallic bonds are some of the important types of chemical bonds. Bond energy and bond length determine the strength of a chemical bond.
Types of Chemical Bonds
An ionic bond is formed due to electrostatic attraction between cations and anions. Often, the ions are formed by the transfer of electrons from...
02:24Polar Covalent Bonds
Covalent bonds are formed between two atoms when both have similar tendencies to attract electrons to themselves (i.e., when both atoms have identical or fairly similar ionization energies and electron affinities). Nonmetal atoms frequently form covalent bonds with other nonmetal atoms. For example, the hydrogen molecule, H2, contains a covalent bond between its two hydrogen atoms. When two separate hydrogen atoms with a particular potential energy approach each other, their valence orbitals...
01:08Covalent Bonds
Overview
When two atoms share electrons to complete their valence shells, they create a covalent bond. An atom's electronegativity—the force with which shared electrons are pulled towards an atom—determines how the electrons are shared. Molecules formed with covalent bonds can be either polar or nonpolar. Atoms with similar electronegativities form nonpolar covalent bonds; the electrons are shared equally. Atoms with different electronegativities share electrons unequally, creating polar bonds.
When two atoms share electrons to complete their valence shells, they create a covalent bond. An atom's electronegativity—the force with which shared electrons are pulled towards an atom—determines how the electrons are shared. Molecules formed with covalent bonds can be either polar or nonpolar. Atoms with similar electronegativities form nonpolar covalent bonds; the electrons are shared equally. Atoms with different electronegativities share electrons unequally, creating polar bonds.