Term: protium
https://doi.org/10.1351/goldbook.P04903

Definition:
A specific name for the atom 1H. The cation 1H+ is a proton, the species 1H is a protide anion, and 1H is the protio group. The word proton should not be used for H+ in its natural abundance.

Related Terms:
1) cation (http://doi.org/10.1351/goldbook.C00907).
2) proton (http://doi.org/10.1351/goldbook.P04906).
3) anion (http://doi.org/10.1351/goldbook.A00358).

Source: PAC, 1988, 60, 1115. 'Names for hydrogen atoms, ions, and groups, and for reactions involving them (Recommendations 1988)' on page 1116 (https://doi.org/10.1351/pac198860071115)

Citation: 'protium' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.P04903

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