通过实验电子密度和光谱测量分子素键的强度
Felix Otte1, Johannes Kleinheider1, Bastian Grabe2
1Inorganic Chemistry, TU Dortmund University, Otto-Hahn-Str. 6, 44227 Dortmund, Germany.
ACS omega
|June 26, 2023
概括
本研究使用各种实验方法研究强和弱素键 (XBs). 研究结果揭示了素键强度如何影响接受原子的原子.
科学领域:
- 超分子化学 超分子化学
- 化学物理 化学物理
- 晶体学 晶体学是指结晶学.
背景情况:
- 素键 (XBs) 是重要的非共价相互作用.
- 了解XB强度及其对受体的影响对于器官催化等应用至关重要.
研究的目的:
- 在离散聚合物中实验性地表征强和弱素键 (XBs).
- 研究XB相互作用对接受原子电子性质的影响.
主要方法:
- 溶液状态核磁共振 (NMR) 定位以确定结合能.
- 拉曼光谱测定C-I拉伸振动和相互作用能量.
- 高分辨率的X射线衍射和分子中的原子量子理论 (QTAIM) 分析电子密度和键性质.
主要成果:
- 对于溶液中的强XBs,测定了大约7kJ/mol的实验性结合能.
- 拉曼光谱证实了C-I振动红移和XB相互作用能量之间的相关性.
- 首次,实验电子密度揭示了接受器 (昆利丁) 的原子体积和贝德尔电荷的显著变化,反映了XB强度.
结论:
- 该研究提供了素键的全面实验性表征,将捐赠体强度与接受器电子修饰联系起来.
- 研究结果表明,XB相互作用明显改变了受体原子的特性,支持它们在XB激活的有机催化中的作用.
相关概念视频
Bond Polarity, Dipole Moment, and Percent Ionic Character
29.0K
Bond Polarity
29.0K
Bond Energies and Bond Lengths
25.4K
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.
25.4K
Molecular Orbital Theory II
19.4K
Molecular Orbital Energy Diagrams
19.4K
Molecular Geometry and Dipole Moments
13.1K
The VSEPR theory can be used to determine the electron pair geometries and molecular structures as follows:
13.1K
Mass Spectrometry: Alkyl Halide Fragmentation
1.1K
Chlorine isotopes exist as 35Cl and 37Cl in a 3:1 ratio, while bromine isotopes exist as 79Br and 81Br in a 1:1 ratio. The mass spectrum of alkyl halides typically produces two distinct molecular ion peaks, the molecular ion peak, [M], and the molecular ion plus two, [M + 2] peak. The relative heights of these two peaks are proportional to the isotopic abundance ratios of the halide. For example, 2‐chloropropane and 1‐bromopropane display two peaks with relative peak heights in a 3:1 and...
1.1K
Intermolecular Forces
58.7K
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen...
58.7K


