The internal energy deposited in the ions in the source of a mass spectrometer governs their fragmentation and therefore the content of the spectra. When the ionization conditions are well defined and reproducible, e.g. in electron impact, the elaboration of databases benefits the use of the method.
Comparison of the internal energy distributions of ions produced by different electrospray sources
✍ Scribed by C. Collette; L. Drahos; E. De Pauw; K. Vékey
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 79 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0951-4198
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✦ Synopsis
The internal energies of the emitted ions can be modulated in an electrospray source through different experimental conditions. However, the fragmentation pattern depends also on conditions that cannot be controlled by the operator, e.g. the geometry of the source or the mode of transfer of the ions. These differences make difficult the comparison of the electrospray mass spectra obtained with different mass spectrometers. A method for the calibration of the internal energies of ions produced by an electrospray source has been presented previously to study the influence of experimental conditions on the internal energies of the ions. The method permits the calibration of individual working conditions. In this work, new results were obtained with modified values of fragmentation energy taking into account the kinetic shift of the thermometer ions. The internal energy distributions are compared for different instruments with different geometries, and are measured under different accelerating and focusing conditions.
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