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Updated: Jul 19, 2026

Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
10:52

Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics

Published on: April 12, 2019

来自C-H,N-H和O-H酸的身份质子转移反应. 一个ab initio,DFT和CPCM-B3LYP水溶剂模型研究

James R Keeffe1, Scott Gronert, Michael E Colvin

  • 1Department of Chemistry and Biochemistry, San Francisco State University, 1600 Holloway Avenue, San Francisco, California 94132, USA.

Journal of the American Chemical Society
|September 18, 2003
PubMed
概括

这项研究研究了质子转移反应,发现气相脱质化度与激活度的相关性很差. 然而,复杂化热量和激活热量显示出良好的相关性,突出了过渡状态稳定因子.

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Interfacial Molecular-level Structures of Polymers and Biomacromolecules Revealed via Sum Frequency Generation Vibrational Spectroscopy

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Technical Approach for Structural Analysis of an Unknown Compound in Huoxiang Zhengqi Oral Liquid based on Linear Ion Trap Mass Spectrometry07:45

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Proton (¹H) NMR: Chemical Shift

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

¹H NMR of Conformationally Flexible Molecules: Temporal Resolution

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...
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Spectroscopy of Carboxylic Acid Derivatives

Infrared spectroscopy is primarily used to determine the types of bonds and functional groups. In carboxylic acid derivatives, a typical carbonyl bond absorption is observed around 1650–1850 cm−1. For esters, the absorption is recorded at around 1740 cm−1, while acid halides show the absorption at about 1800 cm−1. Another acid derivative, the acid anhydrides, exhibit two carbonyl absorption around 1760 cm−1 and 1820 cm−1, arising from the symmetrical and unsymmetrical carbonyl vibration.
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NMR Spectroscopy of Benzene Derivatives01:37

NMR Spectroscopy of Benzene Derivatives

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Chemical Shift: Internal References and Solvent Effects

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