对B-B三重债券优势的实验评估
Julian Böhnke1, Holger Braunschweig, Philipp Constantinidis
1Julius-Maximilians-Universität Würzburg , Am Hubland, 97074 Würzburg, Germany.
Journal of the American Chemical Society
|January 28, 2015
概括
研究人员测量了diborynes的振动频率,证实了它们的-三重键. 这一发现支持diborynes作为真正的三重键,类似于有机分子.
科学领域:
- 无机化学 无机化学
- 频谱学是一种光谱学.
- 计算化学计算化学
背景情况:
- 迪博林是具有-三重键的分子.
- 了解这些同原子键的强度对于表征新型化合物至关重要.
- 之前的研究已经确定了有机化合物和化合物的三重键拉伸频率的趋势.
研究的目的:
- 用拉曼光谱学实验确定diborynes中中央BB单元的拉伸频率.
- 量化评估-三重键的强度.
- 为了比较diborynes与已知的三重键 (例如,CC,NN) 和有机烯的振动特性.
主要方法:
- 拉曼光谱法被用来测量diborynes的振动频率.
- 密度函数理论 (DFT) 建模用于光谱分配和分析.
- 分析了的同位素分布模式,以确认分配.
- 放松力常量被计算用于定量债券强度分析.
主要成果:
- 对diborynes观察到的BB拉伸频率在1600至1750厘米-1.1之间.
- 这些频率与同原子三重键延伸的既定趋势保持一致,包括CC和NN.
- 计算的放松力常数支持将BB单元归类为真正的三重键.
- 一种新合成的具有降低硬质体积的diboryne显示了B2单元的类电子隔离.
结论:
- 振动数据证实了 diborynes 中真正的三重键的存在和强度.
- 迪博林与含有三重键的有机分子具有相似之处,突出显示了第一排p块元素的趋势.
- 这项研究为进一步研究含化合物的化学和结合提供了基础.
相关概念视频
02:49Bond Energies and Bond Lengths
32.7K
Stable molecules exist because covalent bonds hold the atoms together. The strength of a covalent bond is measured by the energy required to break it, that is, the energy necessary to separate the bonded atoms. Separating any pair of bonded atoms requires energy — the stronger a bond, the greater the energy required to break it.
32.7K
02:40Chemical Bonds
24.4K
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...
24.4K
02:45Valence Bond Theory
52.0K
Overview of Valence Bond Theory
52.0K
02:42Valence Bond Theory
11.9K
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...
11.9K
02:13Bond Dissociation Energy and Activation Energy
12.3K
Bond energy is the energy required to break a bond homolytically. These values are usually expressed in units of kcal/mol or kJ/mol and are referred to as bond dissociation energies when given for specific bonds or average bond energies when indicated for a given type of bond over many compounds. Firstly, the bond dissociation energy for a single bond is weaker than that of a double bond, which in turn is weaker than that of a triple bond. Secondly, hydrogen forms relatively strong bonds with...
12.3K
01:08Spin–Spin Coupling Constant: Overview
1.7K
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
1.7K