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Updated: Jun 12, 2025

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
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Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method

Published on: July 19, 2019

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质子位点对碰撞诱导解离的影响-MS/MS 使用CIDMD量子化学建模

Jesi Lee1,2, Dean Joseph Tantillo1, Lee-Ping Wang1

  • 1Department of Chemistry, University of California, Davis, California 95616, United States.

Journal of chemical information and modeling
|September 27, 2024
PubMed
概括

使用碰撞诱导解离分子动力学 (CIDMD) 预测质谱取决于质子位点. 这项研究表明,质子亲和力不能预测光谱精度;相反,在电喷射和碎片化能量障碍期间的质子转移是关键. 多个原质子计算对于精确的in silicoMS/MS预测至关重要.

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Chemical Ionization (CI) Mass Spectrometry

The molecular ion peak of a molecule in the mass spectrum provides vital information for molecular identification. However, conventional electron impact ionization can lead to the rapid dissociation of some molecular ions before they reach the detector. A milder ionization method is required to increase the lifetime of such ionized analyte molecules. Chemical ionization (CI) is a gas-phase protonation reaction useful for mass-analyzing analyte molecules that are easily protonated to yield the...
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When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...
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