Principal ion

Term · Chemistry · MLC-T-CHM-009471

A molecular or fragment ion built from the most abundant isotope of each of its atoms, such as 12C, 1H, 16O and 35Cl. Its mass is the monoisotopic mass of the species, and it is not necessarily the tallest peak in the isotopic cluster, because large molecules and bromine compounds have heavier isotopologues that are more intense. For a compound deliberately enriched in a heavy isotope, the enriched atoms are treated as a separate element.

Table 1. Record
Identifier	MLC-T-CHM-009471
Field	Chemistry
Subject	Physical and Biophysical Chemistry
References	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 1550 (https://doi.org/10.1351/pac199163101541)
See also	Isotopes

Record as JSON

{
  "id": "MLC-T-CHM-009471",
  "term": "Principal ion",
  "field": "Chemistry",
  "definition": "A molecular or fragment ion built from the most abundant isotope of each of its atoms, such as 12C, 1H, 16O and 35Cl. Its mass is the monoisotopic mass of the species, and it is not necessarily the tallest peak in the isotopic cluster, because large molecules and bromine compounds have heavier isotopologues that are more intense. For a compound deliberately enriched in a heavy isotope, the enriched atoms are treated as a separate element.",
  "subject": "Physical and Biophysical Chemistry",
  "see_also": [
    "isotopes"
  ],
  "references": [
    "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 1550 (https://doi.org/10.1351/pac199163101541)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/principal-ion/"
}

Record 10,057 of 13,676 in Chemistry terminology (MLC-0109). Request the full dataset.