How to Interpret a Mass Spectrum with Some Unreasonable Neutral Losses

Considering neutral loss from the molecular ion or a fragment/product ion in mass spectrometry?


As a general rule, loss of 3 to 14 or 21 to 26 is not reasonable in the gas chromatography-mass spectrometry (GC-MS) electron ionization (EI). These are likely to be formed from noise spikes or ions from an impurity.

However, look at the GC-MS EI spectrum of 4,4-Dimethylcyclohexene!



Click to enlarge the image

M = Molecular

Is the infographic easy to understand❓ Let Chemaficionado know at mychemistryhomework@gmail.com❗

References:

(1)    Varian Saturn GC/MS Mass Spectral Interpretation Quick Reference Guide.

(2)    National Institute of Standards and Technology. NIST Chemistry WebBook - SRD 69. NIST. https://webbook.nist.gov/chemistry/.

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