Term: peripheral atom
https://doi.org/10.1351/goldbook.P04497

Definition:
A secondary reference (non-core) atom which at some point in the mechanistic sequence is situated in the molecule containing the core atom(s).

Related Terms:
1) reference (<em>in organic reaction mechanisms</em>) (http://doi.org/10.1351/goldbook.R05227-1).
2) core atom(s) (<em>in organic reaction mechanisms</em>) (<em>in organic reaction mechanisms</em>) (http://doi.org/10.1351/goldbook.C01341).
3) atom (<em>in organic reaction mechanisms</em>) (<em>in organic reaction mechanisms</em>) (<em>in organic reaction mechanisms</em>) (http://doi.org/10.1351/goldbook.R05227-2).
4) sequence (<em>in organic reaction mechanisms</em>) (http://doi.org/10.1351/goldbook.ST06775).

Source: PAC, 1989, 61, 23. 'System for symbolic representation of reaction mechanisms (Recommendations 1988)' on page 27 (https://doi.org/10.1351/pac198961010023)

Citation: 'peripheral atom' 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.P04497

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