# monoisotopicMolecularWeight - Schema.org Property

> Source: https://schema.org/monoisotopicMolecularWeight
> Extracted: 2026-02-16T18:50:15.719Z

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A Schema.org Property

*This term is in the "new" area - implementation feedback and adoption from applications and websites can help improve our definitions.*

The monoisotopic mass is the sum of the masses of the atoms in a molecule using the unbound, ground-state, rest mass of the principal (most abundant) isotope for each element instead of the isotopic average mass. Please include the units in the form '<Number> <unit>', for example '770.230488 g/mol' or as '<QuantitativeValue>.

#### Source

[http://www.bioschemas.org/MolecularEntity](http://www.bioschemas.org/MolecularEntity)