https://doi.org/10.1351/goldbook.I03272
A reaction (actual or hypothetical) in which the types of bonds that are made in forming the products are the same as those which are broken in the reactants, e.g.
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Such processes have advantages for theoretical treatment. The @H02732@ as applied to equilibria [cf. (a)] essentially deals with isodesmic processes.
Source:
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1128 [Terms] [Paper]