Principal ion
From Mass Spec Terms
| DRAFT DEFINITION |
| Principal ion |
|---|
| The most abundant ion of an isotope cluster, such as the 11B79Br281Br+. ion of m/z 250 of the isotope cluster of molecular ions of BBr3. The term principal ion has also been used to describe ions that have been artificially isotopically enriched in one or more positions such as CH3 13CH3+. or CH2D2+, but those are best defined as Isotopologue Ions. |
| Considered between 2004 and 2006 but not included in the 2006 PAC submission |
| This is an unofficial draft definition presented for information and comment. |
Orange Book Entry
This is defined as a {{Molecular Ion|molecular]] or fragment ion which is made up of the most abundant isotopes of each of its atomic constituents. In the case of compounds that have been artificially enriched in one or more positions such as CH3 13CH3 or CH2D2 the principal ion may be defined by treating the heavy isotopes as new atomic species. Thus in the two above example the principal ions would be of masses 13 and 18, respectively.
