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IUPAC - embryo (E02055)

embryo

Also contains definitions of: critical embryo, homogeneous nucleus
https://doi.org/10.1351/goldbook.E02055
An aggregate of a small number of atoms, molecules or ions. An embryo of such a size that the Gibbs energy at constant pressure and temperature is a maximum is called a critical embryo. An embryo larger than a critical embryo is called a homogeneous nucleus. @C01172@ may be formed by condensation methods. When a condensation method is applied, molecules (or ions) are deposited on nuclei which may be of the same chemical species as the @C01171@ (@H02848@) or different (@H02807@).
Source:
PAC, 1972, 31, 577. (Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols in Colloid and Surface Chemistry) on page 608 [Terms] [Paper]