Jove
Visualize
联系我们
JoVE
x logofacebook logolinkedin logoyoutube logo
关于 JoVE
概览领导团队博客JoVE 帮助中心
作者
出版流程编辑委员会范围与政策同行评审常见问题投稿
图书馆员
用户评价订阅访问资源图书馆顾问委员会常见问题
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experiments存档
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教师资源中心教师网站
使用条款与条件
隐私政策
政策

相关概念视频

¹H NMR of Conformationally Flexible Molecules: Temporal Resolution00:52

¹H NMR of Conformationally Flexible Molecules: Temporal Resolution

777
At room temperature, the chair conformer of cyclohexane undergoes rapid ring flipping between two equivalent chair conformers at a rate of approximately 105 times per second. These two chair conformers are in equilibrium. The rapid ring flipping results in the interconversion of the axial proton to an equatorial proton and an equatorial to the axial proton. Such interconversions are too rapid and cannot be detected on the NMR timescale. Hence, the NMR spectrometer cannot distinguish between the...
777
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR01:15

¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR

1.0K
The axial and equatorial protons in cyclohexane can be distinguished by performing a variable-temperature NMR experiment. In this process, except for one proton, the remaining eleven protons are replaced by deuterium. The deuterium substitution avoids the possible peak splitting caused by the spin-spin coupling between the adjacent protons. The remaining proton flips between the axial and equatorial positions.
1.0K
IR Absorption Frequency: Delocalization01:04

IR Absorption Frequency: Delocalization

674
Electron delocalization refers to the distribution of electrons across multiple atoms within a molecule rather than being confined to a single atom or bond. This phenomenon is common in systems with conjugated bonds—structures where alternating single and double bonds allow π-electrons to move freely across the network. The movement of electrons stabilizes the molecule and can affect various chemical properties, including vibrational frequencies observed in IR spectroscopy.
In IR...
674
IR Frequency Region: Fingerprint Region01:03

IR Frequency Region: Fingerprint Region

645
IR spectra are divided into two main regions: the diagnostic region and the fingerprint region. The diagnostic region of the spectrum lies above 1500 cm−1. The absorptions resulting from single-bond vibrations of the N–H, C–H, and O–H stretch at higher wavenumbers and appear on the left side of the spectrum. The stretching absorptions of the C≡C and C≡N occur between 2100–2300 cm−1. In contrast, those arising from stretching absorptions of the...
645
UV–Vis Spectroscopy: Woodward–Fieser Rules01:29

UV–Vis Spectroscopy: Woodward–Fieser Rules

23.1K
UV–Visible absorption spectra of conjugated dienes arise from the lowest energy π → π* transitions. The light-absorbing part of the molecule is called the chromophore, and the substituents directly attached to the chromophore are called auxochromes. A strong correlation exists between the absorption maxima, λmax, and the structure of a conjugated π system. The Woodward–Fieser rules predict the value of λmax for a given...
23.1K
Chair Conformation of Cyclohexane02:02

Chair Conformation of Cyclohexane

14.1K
The chair conformation is the most stable form of cyclohexane due to the absence of angle and torsional strain. The absence of angle strain is a result of cyclohexane’s bond angle being very close to the ideal tetrahedral bond angle of 109.5° in its chair conformer. Similarly, the torsional strain is also absent owing to the perfectly staggered arrangement of bonds.
The hydrogen atoms linked to carbons are arranged in two different axial and equatorial orientations to achieve this...
14.1K

您也可能阅读

相关文章

通过共同作者、期刊和引用图与本文相关的文章。

排序
Same author

Toward Tunable Silver Superatoms. Evaluation of Electronic and Optical Properties of N-Heterocyclic Carbene [Ag<sub>13</sub>Cl<sub>2</sub>(L)<sub>5</sub>]<sup>3+</sup> Clusters.

The journal of physical chemistry letters·2026
Same author

Stability of Some Ternary 13-Atom Icosahedral Clusters Assessed with Geometric, Electronic, and Thermodynamic Criteria.

The journal of physical chemistry. A·2026
Same author

Assessing van der Waals Corrections in the Description of Water Adsorption and Diffusion on Graphene and Hexagonal Boron Nitride.

ACS omega·2026
Same author

The silver Sputnik. Evaluation of the exohedral dynamic in [C<sub>60</sub>M]<sup>+</sup> (M = Cu, Ag, Au).

Chemical communications (Cambridge, England)·2026
Same author

The Dancer in the Dark: Dynamical Motion of Zirconium Carbide Clusters inside Fullerenes.

Inorganic chemistry·2026
Same author

A supramolecular C<sub>60</sub>S<sub>8</sub> adduct: dynamic and interaction energy considerations of an orbiting S<sub>8</sub> motif from MD + EDA calculations.

Dalton transactions (Cambridge, England : 2003)·2026

相关实验视频

Updated: May 9, 2025

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
08:54

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid

Published on: January 25, 2020

5.6K

通过规格变化控制的离子识别:DFT调查

Renato P Orenha1, Ana L O Andrade1, Renato G Rocha1

  • 1Núcleo de Pesquisas em Ciências Exatas e Tecnológicas, Universidade de Franca, Av. Dr. Armando Salles Oliveira 201, Franca, São Paulo 14404-600, Brazil.

ACS omega
|May 5, 2025
PubMed
概括

这项研究表明分子形状如何影响离子识别. 电子捐赠组倾向于阴离子结合,而电子吸收组倾向于阴离子结合,指导特定离子捕获的分子设计.

更多相关视频

Visualizing the Conformational Dynamics of Membrane Receptors Using Single-Molecule FRET
10:59

Visualizing the Conformational Dynamics of Membrane Receptors Using Single-Molecule FRET

Published on: August 17, 2022

3.1K
Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
11:04

Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides

Published on: September 7, 2019

9.1K

相关实验视频

Last Updated: May 9, 2025

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
08:54

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid

Published on: January 25, 2020

5.6K
Visualizing the Conformational Dynamics of Membrane Receptors Using Single-Molecule FRET
10:59

Visualizing the Conformational Dynamics of Membrane Receptors Using Single-Molecule FRET

Published on: August 17, 2022

3.1K
Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
11:04

Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides

Published on: September 7, 2019

9.1K

科学领域:

  • 超分子化学 超分子化学
  • 计算化学的计算化学
  • 材料科学 材料科学 材料科学

背景情况:

  • 离子在材料生产中至关重要,对健康和环境产生影响.
  • 非共价相互作用是控制离子可用性的关键.
  • 了解离子识别机制对于设计功能分子至关重要.

研究的目的:

  • 通过2,6-bis(1,2,3-triazol-4-yl) pyridine分子的两个构造来研究阴离子和阴离子的识别.
  • 分析分子构成和替代物群对离子结合偏好的影响.
  • 阐明控制离子识别的基础电子和静电相互作用.

主要方法:

  • 为了分析,利用了2,6-bis(1,2,3-triazol-4-yl) pyridine的两个不同的分子构造.
  • 使用能量分解分析-化学价值的自然轨道 (EDA-NOCV) 分析.
  • 研究了与各种离子 (Li+,Na+,K+) 和离子 (F-, Cl-, Br-) 的相互作用.

主要成果:

  • 符合条件的显示基于离子大小的优先认可:K+ > Na+ > Li+和Br- > Cl- > F-.
  • 由于更强的静电和轨道相互作用 (N··cation,C-H··anion键),较小的离子被优先识别.
  • 电子捐赠组 (-NH2) 增强了阴离子识别,而电子吸收组 (-NO2) 提高了阴离子识别.

结论:

  • 分子构造和替代剂效应显著调整离子和离子识别.
  • 电子捐赠体的阴离子识别比电子吸收体的阴离子识别更有利.
  • 这些发现为设计具有定制离子结合功能的分子提供了洞察力.