Term: alternant
https://doi.org/10.1351/goldbook.A00249

Definition:
A conjugated system of π-electrons is termed alternant if its atoms can be divided into two sets so that no atom of one set is directly linked to any other atom of the same set. A00249-1.png A00249-2.png

Related Terms:
1) conjugated system (http://doi.org/10.1351/goldbook.C01267).

Images:
1) Not defined (https://goldbook.iupac.org/img/inline/A00249-1.png) 
2) Not defined (https://goldbook.iupac.org/img/inline/A00249-2.png) 

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1082 (https://doi.org/10.1351/pac199466051077)

Citation: 'alternant' 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.A00249

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