In chemistry and physics, a molecular entity, or chemical entity, is "any constitutionally or isotopically distinct atom, molecule, ion, ion pair, radical, radical ion, complex, conformer, etc., identifiable as a separately distinguishable entity". A molecular entity is any singular entity, irrespective of its nature, used to concisely express any type of chemical particle that can exemplify some process: for example, atoms, molecules, ions, etc. can all undergo a chemical reaction.
Chemical species is the macroscopic equivalent of molecular entity and refers to sets or ensembles of molecular entities.
According to IUPAC, "The degree of precision necessary to describe a molecular entity depends on the context. For example 'hydrogen molecule' is an adequate definition of a certain molecular entity for some purposes, whereas for others it is necessary to distinguish the electronic state and/or vibrational state and/or nuclear spin, etc. of the hydrogen molecule."
See also
- New chemical entity
- Chemical Entities of Biological Interest
Notes and references
- IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "molecular entity". doi:10.1351/goldbook.M03986
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In chemistry and physics a molecular entity or chemical entity is any constitutionally or isotopically distinct atom molecule ion ion pair radical radical ion complex conformer etc identifiable as a separately distinguishable entity A molecular entity is any singular entity irrespective of its nature used to concisely express any type of chemical particle that can exemplify some process for example atoms molecules ions etc can all undergo a chemical reaction Chemical species is the macroscopic equivalent of molecular entity and refers to sets or ensembles of molecular entities According to IUPAC The degree of precision necessary to describe a molecular entity depends on the context For example hydrogen molecule is an adequate definition of a certain molecular entity for some purposes whereas for others it is necessary to distinguish the electronic state and or vibrational state and or nuclear spin etc of the hydrogen molecule See alsoNew chemical entity Chemical Entities of Biological InterestNotes and referencesIUPAC Compendium of Chemical Terminology 2nd ed the Gold Book 1997 Online corrected version 2006 molecular entity doi 10 1351 goldbook M03986 This chemistry related article is a stub You can help Wikipedia by expanding it vte
