Title: double-focusing mass spectrometer
Long Title: IUPAC Gold Book - double-focusing mass spectrometer
DOI: 10.1351/goldbook.D01845
Status: current

Definition
An instrument which uses both direction and velocity focusing, and therefore an ion beam of a given mass/charge is brought to a focus when the ion beam is initially diverging and contains ions of the same mass and charge with different translational energies. The ion beam is measured electrically.

Sources
- Orange Book, 2nd ed., p. 201 (https://media.iupac.org/publications/analytical_compendium/)
- PAC, 1991, 63, 1541. 'Recommendations for nomenclature and symbolism for mass spectroscopy (including an appendix of terms used in vacuum technology). (Recommendations 1991)' on page 1545 (https://doi.org/10.1351/pac199163101541)

Other Outputs
- html: https://dev.goldbook.iupac.org/terms/view/D01845/html
- json: https://dev.goldbook.iupac.org/terms/view/D01845/json
- xml: https://dev.goldbook.iupac.org/terms/view/D01845/xml

Citation: Citation: 'double-focusing mass spectrometer' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.D01845
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Accessed: 2026-05-16T18:10:30+00:00