Mass spectra perfluorotributylamine

Fig. 4.37. El mass spectrum of perfluorotributylamine (mass calibrant FC43) to demonstrate unit resolution of a quadmpole analyzer. The expanded views a-c show peaks separated to almost identical degree.

Accurate mass scales (or calibration curves) are generally established by measuring the mass spectrum of a reference compound simultaneously with the spectrum of the sample. The precise mass of every ion in the spectrum of the reference compound is known, so a precise mass correlation is thereby provided. Common reference materials are perfluorokerosene (PFK) and perfluorotributylamine (PFTBA), the mass spectra of which are shown in Figures 3.1 and 3.2, respectively. Since all the ions formed from these compounds contain several fluorine atoms (18.9984) and no hydrogen atoms (1.0078), they have negative mass defects and are well separated from organic ions that normally have positive mass defects. Of course, other chemicals may be used to provide reference masses, as long as the exact masses in its spectrum are known. 

FIGURE 15.15 Mass spectrum of perfluorotributylamine, showing m/z 131 selected for hybrid chemical ionization. 

Figure 8.50 Electron ionization mass spectrum of perfluorotributylamine (PFTBA). inserts show the peak profiles for m/z 69, 219, and 502.

Reference Compounds under Electron Impact Conditions in Mass Spectrometry Major Reference Masses in the Spectrum of Heptacosafluorotributylamine (Perfluorotributylamine)... 

MAJOR REFERENCE MASSES IN THE SPECTRUM OF HEPTACOSAFLUOROTRIBUTYLAMINE (PERFLUOROTRIBUTYLAMINE)... 

See the table Major Reference Masses in the Spectrum ofHeptacosafluorotributylamine (Perfluorotributylamine) in this section for additional details. 

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