Title: macromolecular isomorphism
Long Title: IUPAC Gold Book - macromolecular isomorphism
DOI: 10.1351/goldbook.M03666
Status: current

Definition
Statistical co-crystallization of different constitutional repeating units which may either belong to the same copolymer chains (copolymer isomorphism) or originate from different homopolymer chains (homopolymer isomorphism). Isomorphism is a general term: in the strict sense, the crystal structure is essentially the same throughout the range of compositions; in isodimorphism or isopolymorphism, there are two or more crystal structures, respectively, depending on composition.

Related Terms
- constitutional repeating units: https://goldbook.iupac.org//terms/view/C01286
- copolymer: https://goldbook.iupac.org//terms/view/C01335
- crystallization: https://goldbook.iupac.org//terms/view/C01434
- homopolymer: https://goldbook.iupac.org//terms/view/H02854

Source
- Purple Book, 1st ed., p. 80 (http://old.iupac.org/publications/books/author/metanomski.html)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/M03666/html
- json: https://goldbook.iupac.org/terms/view/M03666/json
- xml: https://goldbook.iupac.org/terms/view/M03666/xml

Citation: Citation: 'macromolecular isomorphism' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.M03666
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Accessed: 2026-07-14T14:55:05+00:00